RFR: bot: add exception type to counter

[Erik Helin]

Hi all,

please review this small patch that adds the `exception` label to the `skara_runner_exceptions` counter. This is useful to be able to query for different kinds of exceptions when viewing this metric.

Thanks,
Erik

-------------

Depends on: https://git.openjdk.java.net/skara/pull/1169

Commit messages:
 - bot: add exception type to counter

Changes: https://git.openjdk.java.net/skara/pull/1170/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=1170&range=00
  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/skara/pull/1170.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/1170/head:pull/1170

PR: https://git.openjdk.java.net/skara/pull/1170