MuonReconstruction - Clean up interfaces

Hi,

in !42383 (merged), I augmented the interfaces of a bunch of tools to directly pipe the EventContext to the extrapolators and ReadHandles. To avoid an even larger changeset, I simply added a second set of methods with the additional argument and made the old methods calling the new ones using Gaudi::Hive::currentContext(). In this MR, I wanted to get rid of the old methods and use the EventContext consistently everywhere.

Further changes:

• ICombinedMuonTrackBuider: Return unique_ptr to Trk::Track objects rather than raw pointers. Fun-fact

   m_trackFitter->standaloneRefit(*selectedTrack,  bs_x, bs_y, bs_z);

compiles, but hilariously crashes. The correct implementation is

  m_trackFitter->standaloneRefit(*selectedTrack, ctx, bs_x, bs_y, bs_z)

So floating-point numbers can be cast to EventContext&?

• MuonClusterSegmentMakerTools: Clang-reformat

• MuonClusterSegmentMakerTools: Thread safety-checker

Closes ATLASRECTS-6361

Adding: @goblirsc for the philosopher of the day