[cpack/jenkins-main] update commit date format string to something that works on all machines

scripts/build/Jenkins/Jenkinsfile

@@ -258,8 +258,8 @@ def CheckoutRepo(boolean disableSubmodules = false) {
     palRm('commitid')
 
     // CHANGE_DATE is used by the installer to provide some ability to sort tagged builds in addition to BRANCH_NAME and CHANGE_ID
-    commitDateFmt = '%%cs'
-    if (env.IS_UNIX) commitDateFmt = '%cs'
+    commitDateFmt = '%%cI'
+    if (env.IS_UNIX) commitDateFmt = '%cI'
 
     palSh("git show -s --format=${commitDateFmt} ${env.CHANGE_ID} > commitdate", 'Getting commit date')
     env.CHANGE_DATE = readFile file: 'commitdate'

scripts/build/tools/generate_build_tag.py

@@ -66,7 +66,8 @@ if __name__ == "__main__":
     # include the commit date to allow some sensible way of sorting
     commit_date = os.environ.get('CHANGE_DATE')
     if not commit_date:
-        commit_date = run_git_command(['show', '-s', '--format=%cs', commit_hash], repo_root)
+        commit_date = run_git_command(['show', '-s', '--format=%cI', commit_hash], repo_root)
+    commit_date = commit_date[0:10]
 
     print(f'{branch}/{commit_date}-{commit_hash}')
     exit(0)