[gnome-initial-setup] build: use git-evtag if available

[Will Thompson <wjt src gnome org>]

commit 696c36a6129f57c395bf8c876a189d196ef2c585
Author: Will Thompson <wjt endlessm com>
Date:   Mon Apr 27 14:05:01 2020 +0100

    build: use git-evtag if available
    
    Thanks to Philip Withnall for the suggestion

 build-aux/maintainer-upload-release | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/build-aux/maintainer-upload-release b/build-aux/maintainer-upload-release
index 8da13d2..3893c5b 100755
--- a/build-aux/maintainer-upload-release
+++ b/build-aux/maintainer-upload-release
@@ -17,7 +17,13 @@ pushd "$MESON_SOURCE_ROOT"
         echo "Project version $project_version does not match branch $branch" >&2
         exit 1
     fi
-    git tag -s "$project_version" -m "Version $project_version"
+    if type git-evtag &>/dev/null; then
+        # Can't specify tag message on command line
+        # https://github.com/cgwalters/git-evtag/issues/9
+        EDITOR=true git evtag sign "$project_version"
+    else
+        git tag -s "$project_version" -m "Version $project_version"
+    fi
     git push --atomic origin "$branch" "$project_version"
 popd