Automatically disable test timeout when running in a debugger.
(cherry picked from commit abf335933388f0ce28edfb86dbe80972f3280e47)
[JENKINS-23365] Follow-up API fixes: introduce SCM.getKey(), and add an SCMRevisionState baseline argument to checkout.
Necessary in order to produce correct changelogs by SCM plugins which actually use SCMRevisionState correctly (unlike git-plugin!).
(cherry picked from commit df9dc4c850374daeeda72ee37177ba1fe2bcebd6)