keepalive: split the step that creates and pushes a commit into two

The next commit will skip the commit creation under certain
circumstances, which will be more obvious when those steps are separate.

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

Author: dscho

.github/workflows/keepalive.yml

@@ -17,13 +17,15 @@ jobs:
       - uses: actions/checkout@v4
         with:
           persist-credentials: 'true'
-      - name: Create and push a commit
+      - name: Create a commit
         run: |
           mkdir -p .github/cached
           file='.github/cached/keepalive.txt'
           date >$file
           git add "$file"
-          git commit -m "workflow keepalive" &&
+          git commit -m "workflow keepalive"
+      - name: Push changes
+        run: |
           git push origin HEAD </dev/null || {
             for i in 1 2 3 4 5
             do