Script updates.

- add a mode to disable finalization steps if they were already merged,
- add the extension version into commit message.

Bug: 243966946
Test: local run
Change-Id: I51505e5d5715b56f3b385d714e1aabaae06f58ed

tools/finalization/update-step-1.sh

@@ -1,6 +1,9 @@
 #!/bin/bash
 # Script to perform a 1st step of Android Finalization: API/SDK finalization, update CLs and upload to Gerrit.
 
+# WIP, does not work yet
+exit 10
+
 set -ex
 
 function update_step_1_changes() {