Clean up .appimage build script output

[nklayman]

Is your feature request related to a problem? Please describe.
The .deb build script just outputs a nice bundling "[FILE]", while the .appimage build script outputs this mess:

info: running build_appimage.sh
+ export ARCH=x86_64
+ ARCH=x86_64
+ mkdir -p theia.AppDir
+ cp -r ../deb/theia_0.1.0_amd64/data/usr theia.AppDir
+ cd theia.AppDir
+ wget -q -O AppRun https://github.com/AppImage/AppImageKit/releases/download/continuous/AppRun-x86_64
+ chmod +x AppRun
+ cp usr/share/icons/hicolor/256x256/apps/theia.png theia.png
+ cd ..
+ echo '[Desktop Entry]'
+ echo Version=1.0
+ echo 'Comment=A Tauri App'
+ echo Exec=theia
+ echo Icon=theia
+ echo Name=THEIA
+ echo Terminal=false
+ echo Type=Application
+ echo 'Categories=X-Web;'
+ cp theia.desktop theia.AppDir/usr/share/applications/theia.desktop
+ mv theia.desktop theia.AppDir/theia.desktop
+ mksquashfs theia.AppDir theia.squashfs -root-owned -noappend
Parallel mksquashfs: Using 16 processors
Creating 4.0 filesystem on theia.squashfs, block size 131072.
[=============================================================\] 1598/1598 100%

Exportable Squashfs 4.0 filesystem, gzip compressed, data block size 131072
	compressed data, compressed metadata, compressed fragments,
	compressed xattrs, compressed ids
	duplicates are removed
Filesystem size 63590.30 Kbytes (62.10 Mbytes)
	31.39% of uncompressed filesystem size (202561.36 Kbytes)
Inode table size 4660 bytes (4.55 Kbytes)
	59.94% of uncompressed inode table size (7774 bytes)
Directory table size 425 bytes (0.42 Kbytes)
	39.87% of uncompressed directory table size (1066 bytes)
Number of duplicate files found 3
Number of inodes 45
Number of files 18
Number of fragments 1
Number of symbolic links  0
Number of device nodes 0
Number of fifo nodes 0
Number of socket nodes 0
Number of directories 27
Number of ids (unique uids + gids) 1
Number of uids 1
	root (0)
Number of gids 1
	root (0)
+ wget -q -O appimagetool https://github.com/AppImage/AppImageKit/releases/download/continuous/appimagetool-x86_64.AppImage
+ chmod +x appimagetool
+ lsmod
+ grep -q fuse
+ ./appimagetool --appimage-extract
squashfs-root/.DirIcon
squashfs-root/AppRun
squashfs-root/appimagetool.desktop
squashfs-root/appimagetool.png
squashfs-root/usr
squashfs-root/usr/bin
squashfs-root/usr/bin/AppRun
squashfs-root/usr/bin/appimagetool
squashfs-root/usr/bin/desktop-file-validate
squashfs-root/usr/bin/zsyncmake
squashfs-root/usr/lib
squashfs-root/usr/lib/appimagekit
squashfs-root/usr/lib/appimagekit/mksquashfs
squashfs-root/usr/lib/libffi.so.5
squashfs-root/usr/lib/libgio-2.0.so
squashfs-root/usr/lib/libgio-2.0.so.0
squashfs-root/usr/lib/libgio-2.0.so.0.5600.0
squashfs-root/usr/lib/libglib-2.0.so
squashfs-root/usr/lib/libglib-2.0.so.0
squashfs-root/usr/lib/libglib-2.0.so.0.5600.0
squashfs-root/usr/lib/libgmodule-2.0.so
squashfs-root/usr/lib/libgmodule-2.0.so.0
squashfs-root/usr/lib/libgmodule-2.0.so.0.5600.0
squashfs-root/usr/lib/libgobject-2.0.so
squashfs-root/usr/lib/libgobject-2.0.so.0
squashfs-root/usr/lib/libgobject-2.0.so.0.5600.0
squashfs-root/usr/lib/libgthread-2.0.so
squashfs-root/usr/lib/libgthread-2.0.so.0
squashfs-root/usr/lib/libgthread-2.0.so.0.5600.0
squashfs-root/usr/lib/libpcre.so
squashfs-root/usr/lib/libpcre.so.1
squashfs-root/usr/lib/libpcre.so.1.2.11
squashfs-root/usr/lib/libpcrecpp.so
squashfs-root/usr/lib/libpcrecpp.so.0
squashfs-root/usr/lib/libpcrecpp.so.0.0.1
squashfs-root/usr/lib/libpcreposix.so
squashfs-root/usr/lib/libpcreposix.so.0
squashfs-root/usr/lib/libpcreposix.so.0.0.6
squashfs-root/usr/share
squashfs-root/usr/share/applications
squashfs-root/usr/share/applications/appimagetool.desktop
squashfs-root/usr/share/icons
squashfs-root/usr/share/icons/hicolor
squashfs-root/usr/share/icons/hicolor/128x128
squashfs-root/usr/share/icons/hicolor/128x128/apps
squashfs-root/usr/share/icons/hicolor/128x128/apps/appimagetool.png
squashfs-root/usr/share/metainfo
squashfs-root/usr/share/metainfo/appimagetool.appdata.xml
+ ./squashfs-root/AppRun theia.AppDir theia.AppImage
appimagetool, continuous build (commit 0880085), build 2133 built on 2020-07-09 12:25:52 UTC
Using architecture x86_64
Deleting pre-existing .DirIcon
Creating .DirIcon symlink based on information from desktop file
WARNING: AppStream upstream metadata is missing, please consider creating it
         in usr/share/metainfo/theia.appdata.xml
         Please see https://www.freedesktop.org/software/appstream/docs/chap-Quickstart.html#sect-Quickstart-DesktopApps
         for more information or use the generator at http://output.jsbin.com/qoqukof.
Generating squashfs...
Parallel mksquashfs: Using 16 processors
Creating 4.0 filesystem on theia.AppImage, block size 131072.
[=============================================================\] 1598/1598 100%

Exportable Squashfs 4.0 filesystem, gzip compressed, data block size 131072
	compressed data, compressed metadata, compressed fragments,
	compressed xattrs, compressed ids
	duplicates are removed
Filesystem size 63590.34 Kbytes (62.10 Mbytes)
	31.39% of uncompressed filesystem size (202561.42 Kbytes)
Inode table size 4686 bytes (4.58 Kbytes)
	60.02% of uncompressed inode table size (7807 bytes)
Directory table size 436 bytes (0.43 Kbytes)
	40.30% of uncompressed directory table size (1082 bytes)
Number of duplicate files found 3
Number of inodes 46
Number of files 18
Number of fragments 1
Number of symbolic links  1
Number of device nodes 0
Number of fifo nodes 0
Number of socket nodes 0
Number of directories 27
Number of ids (unique uids + gids) 1
Number of uids 1
	root (0)
Number of gids 1
	root (0)
Embedding ELF...
Marking the AppImage as executable...
Embedding MD5 digest
Success

Please consider submitting your AppImage to AppImageHub, the crowd-sourced
central directory of available AppImages, by opening a pull request
at https://github.com/AppImage/appimage.github.io
/home/noah/Documents/html/theia2/examples/tauri/src-tauri/target/release/bundle/appimage/theia.AppDir should be packaged as theia.AppImage
+ rm -rf ./squashfs-root`

Describe the solution you'd like
IMO, the .appimage build script should have the same output as the .deb as to not clutter terminal output. The current output from it feels really out of place and TMI.

[lucasfernog]

The .deb bundling is pure Rust, it doesn`t use any shell scripting. The appimage script has that kind of verbose output because it's difficult for the end user to find where it's failing in case it does. We could change it to show the output only it it fails though

[lucasfernog]

If you wanna give it a try, just play with the execute_with_output function on the common.rs file.