Fix clang compile error: constexpr and std::sqrt

Unfortunately clang doesn't support constexpr sqrt because it isn't in the official standard yet.

added bugfix label

This merge request affects 1 package:

• MuonSpectrometer/MuonCalib/MdtCalib/MdtCalibSvc

Adding @rosati ,@nkoehler ,@wleight as watchers

added MuonSpectrometer master review-pending-level-1 labels

CI Result SUCCESS (hash 19d43d19)

	Athena	AthSimulation	AthGeneration	AnalysisBase
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
AthGeneration: number of compilation errors 0, warnings 0
AnalysisBase: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 19383]

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

merged

mentioned in commit b1603c2c

added sweep:ignore label

mentioned in merge request !35932 (closed)