git-artifacts: really accommodate for split mingw-w64-git package

Copy/pasta snafu.

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

Author: dscho

.github/workflows/git-artifacts.yml

@@ -167,7 +167,7 @@ jobs:
             --version=$(cat pkg-${{env.ARCH_NAME}}/ver) \
             -o artifacts \
             --${{matrix.artifact}} \
-            $(ls pkg-$ARCH_NAME/$MINGW_PACKAGE_PREFIX-*.pkg.tar.* |
+            $(ls pkg-$ARCH_NAME/mingw-w64-*.pkg.tar.* |
               sed '/\.sig$/d;/archimport/d;/cvs/d;/p4/d;/gitweb/d;/doc-man/d;s/^/--pkg=/')
       - name: Copy package-versions and pdbs
         if: matrix.artifact == 'installer'