MuonOverlayBase+CscOveray+MdtOverlay: Fix cppcheck warnings.

Ignored function return values.

This merge request affects 3 packages:

• MuonSpectrometer/MuonOverlay/CscOverlay
• MuonSpectrometer/MuonOverlay/MdtOverlay
• MuonSpectrometer/MuonOverlay/MuonOverlayBase

Affected files list will not be printed in this case

Adding @jchapman ,@rosati ,@stavrop ,@kluit ,@jojungge ,@ahaas ,@tkharlam ,@apsallid ,@pscholer ,@tadej as watchers

added MuonSpectrometer Overlay main review-pending-level-1 labels

CI Result SUCCESS (hash 76d8ad28)

	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 79201]

added review-approved label

removed review-pending-level-1 label

merged

mentioned in commit c980e782

added sweep:ignore label