Suggestions about creating release

[Growl1234]

Hi devs,

I'd like to ask that would it be better to give a seperated tarball rather than just "Source code (zip/tar.gz)" when creating a release?

Several small suggestions moreover:

1. There's currently a submodule "deps/libpaw_interface", and it wouldn't be truly included with downloading either from "Source code (zip/tar.gz)" at release pages or via "Code/Download ZIP". When creating such a tarball we can leverage git clone --recursive to contain that tree in the ABACUS source tree.
2. Include some files as export-ignored in a .gitattributes file, thus these files can be skipped when downloading via "Code/Download ZIP", and when checking the released tarball these files can also be removed. (No benefits nor harm, just to make source tree a bit cleaner)
3. You can use another format such as tar.xz with a higher compression ratio, thereby substantially reducing upload and download overhead.

An example of .gitattributes in suggestion 2 would be like:

.gitattributes export-ignore
.gitignore export-ignore
.gitmodules export-ignore
.pre-commit-config.yaml export-ignore
.github/ export-ignore

[mohanchen]

Great! Your suggestions are helpful. Thanks, we will consider that.