XML Filename Pattern dropped when Updating Jenkins Configuration

When I update the configuration for a Jenkins job that uses the Violations plugin, the xml filename pattern gets removed from the textbox upon saving the new configuration.

Reproduce the issue by editing a Jenkins job that uses the Violations plugin and saving its configuration. Trace how the XML filename pattern is loaded and persisted during configuration updates. Done means the pattern remains in the textbox after saving and reopening the job configuration.

Written by the indexing model from the issue text.