SGTools: Move static variable out-of-line.

Move the empty string variable used in TransientAddress::name() from being defined in that inlined method to a static class member which is instead defined out-of-line.

Avoids crashes seen related to library loading ordering when compiled with LTO.

added full-unit-tests label

This merge request affects 1 package:

• Control/SGTools

This merge request affects 2 files:

• Control/SGTools/SGTools/TransientAddress.h
• Control/SGTools/src/TransientAddress.cxx

Adding @ssnyder as watcher

added Core main review-pending-level-1 labels

CI Result SUCCESS (hash 9e6992ce)

	Athena	AthSimulation	AthGeneration	AthAnalysis
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
AthSimulation: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 8463] (remote access info)

removed review-pending-level-1 label

added review-approved label

merged

mentioned in commit 6be002a0