open-pr(msys2-runtime): use a nicer commit message

The commit message is technically correct, but it lists the full OID of
the `msys2/msys2-runtime` commit, which is not very helpful.

Let's instead use the package version as documented in the `PKGBUILD`
file in the commit message.

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

Author: dscho

.github/workflows/open-pr.yml

@@ -118,7 +118,12 @@ jobs:
           update_script="$GITHUB_WORKSPACE/update-scripts/version/$PACKAGE_TO_UPGRADE"
           if test -f "$update_script"
           then
-            $update_script "$UPGRADE_TO_VERSION"
+            $update_script "$UPGRADE_TO_VERSION" &&
+            if test -f UPGRADE_TO_VERSION
+            then
+              UPGRADE_TO_VERSION="$(cat UPGRADE_TO_VERSION)" &&
+              rm UPGRADE_TO_VERSION
+            fi
           else
             sed -i \
               -e "s/^\\(pkgver=\\).*/\\1$UPGRADE_TO_VERSION/" \

update-scripts/version/msys2-runtime

@@ -76,4 +76,6 @@ if test -n "$update_pkgver"
 then
     git reset --soft HEAD^ &&
     sed -i 's/^pkgrel=.*/pkgrel=1/' PKGBUILD
-fi
+fi &&
+sed -n '/^pkgver=/{:1;N;/pkgrel=/{s/.*pkgver=\([0-9\.]*\).*pkgrel=\([0-9]*\).*/\1-\2/p;q};b1}' \
+    <PKGBUILD >UPGRADE_TO_VERSION