roll_util: Filter auto submit tags

Change-Id: Ie40ed8138f62956b85a8804266cce557c158fc05
Reviewed-on: https://pigweed-review.googlesource.com/c/infra/recipes/+/25220
Pigweed-Auto-Submit: Rob Mohr <mohrr@google.com>
Reviewed-by: Nathan Mulcahey <nmulcahey@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/recipe_modules/roll_util/api.py b/recipe_modules/roll_util/api.py
index 3ece600..3a07523 100644
--- a/recipe_modules/roll_util/api.py
+++ b/recipe_modules/roll_util/api.py
@@ -42,9 +42,17 @@
     'Signed-off-by:',
     'Testability-Review:',
     'Tested-by:',
+    'Auto-Submit',
+    re.compile(r'^\w+-Auto-Submit:'),
 ]
 
 
+def _match_tag(line, tag):
+    if hasattr(tag, 'match'):
+        return tag.match(line)
+    return line.startswith(tag)
+
+
 def _sanitize_message(message):
     """Sanitize lines of a commit message.
 
@@ -56,7 +64,7 @@
         if any((line.startswith(tag) for tag in ESCAPE_TAGS))
         else line
         for line in message.splitlines()
-        if not any((tag in line for tag in FILTER_TAGS))
+        if not any((_match_tag(line, tag) for tag in FILTER_TAGS))
     )