appveyor.yml - update for msys2 - pdcurses, force toolchain

Closes: #2208

Merging the PR for fixing AppVeyor msys2 failure related to GCC 9 like:
https://ci.appveyor.com/project/ruby/ruby/builds/24877992/job/ned5k4k5rwxnld5j

appveyor.yml

@@ -99,8 +99,10 @@ for:
   build_script:
     # always update database
     - pacman -Sy
-    - pacman -S --noconfirm --needed --noprogressbar mingw-w64-x86_64-toolchain
-    - pacman -S --noconfirm --needed --noprogressbar mingw-w64-x86_64-gdbm mingw-w64-x86_64-gmp mingw-w64-x86_64-libffi mingw-w64-x86_64-ncurses mingw-w64-x86_64-readline mingw-w64-x86_64-zlib
+    - pacman -S --noconfirm --needed --noprogressbar --nodeps mingw-w64-x86_64-toolchain
+    # 2019-May-29 delete below after next Appveyor msys2 update, above line remove '--nodeps'
+    - pacman -S --noconfirm --needed --noprogressbar mingw-w64-x86_64-python3 mingw-w64-x86_64-readline mingw-w64-x86_64-sqlite3
+    - pacman -S --noconfirm --needed --noprogressbar mingw-w64-x86_64-gdbm mingw-w64-x86_64-gmp mingw-w64-x86_64-libffi mingw-w64-x86_64-openssl mingw-w64-x86_64-pdcurses mingw-w64-x86_64-readline mingw-w64-x86_64-zlib
     - cd %APPVEYOR_BUILD_FOLDER%
     - set CFLAGS=-march=%MSYS2_ARCH:_=-% -mtune=generic -O3 -pipe
     - set CXXFLAGS=%CFLAGS%