Add cache rootfs creation cleanup for old files to Github Actions (#2947)

.github/workflows/build.yml

@@ -121,7 +121,7 @@ jobs:
             gpg-private-key: ${{ secrets.GPG_KEY1 }}
             passphrase: ${{ secrets.GPG_PASSPHRASE1 }}
 
-        - name: Sign commit and push changes
+        - name: Cleanup and sign rootfs cache
 
           if: ${{ success() }}
           env:
@@ -131,6 +131,13 @@ jobs:
             sudo apt-get -y -qq install parallel
             cd build/cache/rootfs
             sudo chown -R $USER:$USER .
+            # cleanup
+            for line in $(ls | cut -d. -f1-4 | sort -u); do
+                if [[ ! -f $line ]]; then
+                    [[ -n "$line" ]] && rm -f "$line"*
+                fi
+            done
+            # sign
             (for file in $(ls | cut -d. -f1-4 | sort -u); do
                 if [ $(ls $file* | wc -l) -lt 3 ]; then
                    echo "$file"