ForwardTracker: Fix cppcheck 2.14 warnings.

Prefer returning const references to members rather than copies. Pass object by const reference, not by value.

This merge request affects 1 package:

• ForwardDetectors/ForwardTracker

This merge request affects 2 files:

• ForwardDetectors/ForwardTracker/ForwardTracker/ForwardTrack.h
• ForwardDetectors/ForwardTracker/src/ForwardTrack.cxx

added ForwardDetectors main review-pending-level-1 labels

CI Result SUCCESS (hash 2382c2ce)

	Athena
externals
cmake
make
tests

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Athena: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 9538] (remote access info)

Looks good, approving --L1

added review-approved label and removed review-pending-level-1 label

mentioned in commit 3bac0415

merged