pytester: LineMatcher: __tracebackhide__ with _fail
pytester: LineMatcher: __tracebackhide__ with _fail

Follow-up to 2228ccb (gone lost in resolving the conflict).

The-Compiler/pytest,markshao/pytest,Akasurde/pytest,RonnyPfannschmidt/pytest,nicoddemus/pytest,The-Compiler/pytest,nicoddemus/pytest,pytest-dev/pytest,alfredodeza/pytest