Fix Jenkins plugin filling commits when referencing wrong JIRA issue

When a wrong JIRA issue is filled in a commit, and other valid commits are handled in the same build, valid commits should still be handled correctly.

For instance here:
http://qa.nuxeo.org/jenkins/job/nuxeo-master/194/

There are 4 commits, including an invalid JIRA reference (NXP-16469)

NXP-16338: Remove ANONYMOUS_AUTH plugin from 'Automation' and 'RestAPI' specific authentication chains (commit: c15b08227fe4b31092c42c814b4f7c616c2cee93) (detail / githubweb)
NXP-16469: remove old template handling print view, not used anymore (commit: baed50ebcf5898a226d1491528ddff5b2b8d1ac2) (detail / githubweb)
NXP-16238: fix exposure of nxu:valueHolder tag on restore phase, when value is not exposed on the bean (by fallbacking on the component default value) (commit: b6ac2c9739391904045b313136c1f84411bcb3d5) (detail / githubweb)
NXP-16368: move layout id counters to a managed bean (commit: 63c289b938c2c4ed727d3a0af16f56b035ec403b) (detail / githubweb)
NXP-16368: when dumping request in case of error, remove filtering of request attributes that are not exposed to the request anymore (moved to managed beans) (commit: f6c4ba8d4f045ed73574710e51c7682602b1c3a1) (detail / githubweb)

Logs say

20:00:13 Error updating JIRA issues. Saving issues for next build.
20:00:13 com.atlassian.jira.rpc.exception.RemotePermissionException: This issue does not exist or you don't have permission to view it.