infra: be more flexible when recognizing test commits in the release …

…bump script

They can now have, test:, tests: prefix, or (#test), (#tests) string in
commit message.

Cherry-picked from master commit 5d1b1bb

scripts/makebumpver

@@ -302,7 +302,7 @@ class MakeBumpVer:
                 print("*** Ignoring (#infra) commit %s\n" % commit)
                 continue
 
-            if re.match(r".*(#test).*", summary):
+            if re.match(r".*(#test[s]).*", summary) or re.match(r"test[s]: .*", summary):
                 print("*** Ignoring (#test) commit %s\n" % commit)
                 continue