DecisionHandling+TrigPartialEventBuilding: remove support for legacy menu

Remove legacy configuration support.

added full-unit-tests label

This merge request affects 2 packages:

• Trigger/TrigAlgorithms/TrigPartialEventBuilding
• Trigger/TrigSteer/DecisionHandling

Affected files list will not be printed in this case

Adding @tamartin ,@fpastore as watchers

added 24.0 Trigger review-pending-level-1 labels

CI Result FAILURE (hash 06553a80)

	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-EL9 5007]

Unrelated unit test failures.

removed review-pending-level-1 label

added review-approved-point1 label

added review-approved label

mentioned in commit 0bb9eb1f

merged

mentioned in merge request !69125 (merged)