ComponentAccumulator: fix and extend gatherProps unit test

Fix the gatherProps unit test (was not running at all) and extend it to check ordering of the new set properties in Gaudi v38.

This merge request affects 1 package:

• Control/AthenaConfiguration

This merge request affects 2 files:

• Control/AthenaConfiguration/python/ComponentAccumulator.py
• Control/AthenaConfiguration/test/testComponentAccumulator.py

Adding @maszyman ,@gemmeren ,@ssnyder as watchers

added Core analysis-review-required full-unit-tests main review-pending-level-1 labels

CI Result SUCCESS (hash 52853f4c)

	Athena	AthSimulation	AthGeneration	AnalysisBase	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
AnalysisBase: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 4123]

removed analysis-review-required label

removed review-pending-level-1 label

added review-approved label

merged

mentioned in commit e4248d4b