Describe the bug
When building via the Maven UI it doesn't populate Problems, because VS Code Maven extension doesn't contribute a ProblemMatcher.

To Reproduce
Steps to reproduce the behavior:

1. open a maven project
2. perform any action via Maven UI
3. If problems are produced by Maven they aren't reflected in the Problems

Expected behavior
VS Code Maven should contribute a ProblemMatcher.

Additional context
Derived from #1097 and from redhat-developer/vscode-java#4117