MuonHoughPatternTool::printPattern: add check on validity of provided pointer

Athena crashes with a segfault in MuonHoughPatternTool when setting the VERBOSE logging level. This MR fixes the issue. Possibly @jojungge may want to comment.

added 23.0 MuonSpectrometer bugfix labels

This merge request affects 1 package:

• MuonSpectrometer/MuonReconstruction/MuonPatternFinders/MuonPatternFinderTools/MuonHoughPatternTools

This merge request affects 1 file:

• MuonSpectrometer/MuonReconstruction/MuonPatternFinders/MuonPatternFinderTools/MuonHoughPatternTools/src/MuonHoughPatternTool.cxx

Adding @apsallid ,@goetz ,@rosati ,@pscholer ,@stavrop ,@jojungge as watchers

added review-pending-level-1 label

added review-approved label

removed review-pending-level-1 label

CI Result SUCCESS (hash 5d8383e9)

	Athena
externals
cmake
make
tests

Full details available on this CI monitor view. Check the JIRA CI status board for known problems
Athena: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 74133]

added review-approved-point1 label

added review-approved-tier0 label

mentioned in commit 4006e569

merged

mentioned in merge request !64264 (merged)

mentioned in merge request !64443 (merged)