RugneKuttaUtils : Make things that can be const , const

This came up as was going through code to understand some GSF calls. It is not biggy, but it does not hurt either to have things that are const marked as const

This merge request affects 1 package:

• Tracking/TrkExtrapolation/TrkExUtils

Adding @amorley as watcher

added Tracking master review-pending-level-1 labels

CI Result SUCCESS (hash 330736b2)

	Athena	AthSimulation
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
Athena: number of compilation errors 0, warnings 0
AthSimulation: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 6035]

Looks good to me, approving --L1

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

merged

mentioned in commit 83cfa82c

added sweep:ignore label