[test/message] Allow numbers to have more than one leading digit.

The {NUMBER} regexp only allowed one, leading to occasional test
failures such as:
https://build.chromium.org/p/client.v8/builders/V8%20Mac%20-%20debug/builds/17156

Bug: 
Change-Id: I25a08b80640d9af19ba70c61c846163685f1cb82
Reviewed-on: https://chromium-review.googlesource.com/753322Reviewed-by: Franziska Hinkelmann <franzih@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49109}

test/message/testcfg.py

@@ -120,7 +120,7 @@ class MessageTestSuite(testsuite.TestSuite):
         expected_lines, actual_lines, fillvalue=''):
       pattern = re.escape(expected.rstrip() % env)
       pattern = pattern.replace("\\*", ".*")
-      pattern = pattern.replace("\\{NUMBER\\}", "\d(?:\.\d*)?")
+      pattern = pattern.replace("\\{NUMBER\\}", "\d+(?:\.\d*)?")
       pattern = "^%s$" % pattern
       if not re.match(pattern, actual):
         return True