fix: dev: [gogocarto] don't fail if no change in last code version

If we loose the `.version` file for some reason (this should not
happen). Don't try to commit an empty commit.

Signed-off-by: Valentin Lab <valentin.lab@kalysto.org>

gogocarto/lib/common

@@ -37,8 +37,18 @@ gogocarto:init() {
             return 1
         }
         echo "$GOGOCARTO_RELEASE" > .version
-        git add -A . &&
-            git commit -m "Release $GOGOCARTO_RELEASE"
+        git add -A . || {
+            err "'git add -A .' in '${GOGOCARTO_CODE}' failed."
+            return 1
+        }
+        if git diff --staged -s --exit-code; then
+            info "No differences with last saved version."
+        else
+            git commit -m "Release $GOGOCARTO_RELEASE" || {
+                err "'git commit' failed."
+                return 1
+            }
+        fi
     fi
 }