makepkg-git: use AsciiDoctor again

In #6, we switched
the `makepkg-git` SDK artifact in git-sdk-arm64 away from using
AsciiDoctor to using AsciiDoc instead. The reason was that the former
was not yet supported in the `clangarm64` packages in MSYS2.

In the meantime, AsciiDoctor is not only supported, but now also
required to build `mingw-w64-clang-aarch64-git`.

So let's adjust the `makepkg-git` sparse checkout definition
accordingly.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

.sparse/makepkg-git

@@ -60,16 +60,33 @@
 # The `error_highlight` Ruby gem, needed by `asciidoctor`
 *error_highlight*
 
-# AsciiDoc
-/clangarm64/bin/asciidoc.exe
-/clangarm64/bin/asciidoc-script.py
-/clangarm64/bin/python*
-/clangarm64/bin/libpython*.dll
-/clangarm64/lib/python*/
-!/clangarm64/lib/python*/site-packages/
-!/clangarm64/lib/python*/test/
-/clangarm64/lib/python*/site-packages/asciidoc/
-/clangarm64/lib/python*/site-packages/asciidoc*-info/
+# AsciiDoctor
+/clangarm64/bin/asciidoctor
+/clangarm64/bin/ruby.exe
+/clangarm64/bin/ruby*.dll
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/rbconfig.rb
+/clangarm64/lib/ruby/*/rubygems.rb
+/clangarm64/lib/ruby/*/rubygems/
+/clangarm64/lib/ruby/*/delegate.rb
+/clangarm64/lib/ruby/*/uri.rb
+/clangarm64/lib/ruby/*/uri/
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/stringio.so
+/clangarm64/lib/ruby/*/monitor.rb
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/monitor.so
+/clangarm64/lib/ruby/gems/*/gems/asciidoctor-*
+/clangarm64/lib/ruby/gems/*/specifications/asciidoctor-*.gemspec
+/clangarm64/lib/ruby/*/tsort.rb
+/clangarm64/lib/ruby/*/set.rb
+/clangarm64/lib/ruby/*/logger.rb
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/enc/encdb.so
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/enc/windows_1252.so
+/clangarm64/lib/ruby/*/optparse.rb
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/strscan.so
+/clangarm64/lib/ruby/*/pathname.rb
+/clangarm64/lib/ruby/*/aarch64-mingw-ucrt/pathname.so
+/clangarm64/lib/ruby/*/did_you_mean*
+/clangarm64/lib/ruby/*/cgi/util*
+/clangarm64/lib/ruby/*/logger*
 
 # xsltproc (e.g. for Git's user-manual.html)
 /usr/bin/xsltproc.exe