ALFA_G4_SD+ZDC_SD: Fix thread-safety checker warnings.

Disable thread-safety checking for code using gtest. Fixes (disabled-by-default) warnings about calls to unchecked code.

This merge request affects 2 packages:

• ForwardDetectors/ALFA/ALFA_G4_SD
• ForwardDetectors/ZDC/ZDC_SD

Affected files list will not be printed in this case

Adding @lshan ,@battagl ,@stsuno as watchers

added ForwardDetectors Simulation master review-pending-level-1 labels

CI Result SUCCESS (hash 260413be)

	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-CC7 62733]

removed review-pending-level-1 label

added review-approved label

merged

mentioned in commit 5be21fbc

added sweep:ignore label