Read BDT score from first 12 bits of xTOB

The BDT score is read from the first 11 bits of word 0 of the xTOB while it should be read from the first 12 bits instead, since the padding MSB bits are all 0 if the BDT score takes less than 12 bits. For now there were no issues with this since the BDT score takes only 11 bits, but the purpose of this fix is to avoid issues in the future if the BDT is re-trained and would result in a 12-bit BDT score, in which case the MSB bit would have been ignored.

See https://indico.cern.ch/event/1354773/contributions/5704602/attachments/2769314/4824688/2023-12-11.pdf, slide 6

This was tested by running a derivation with and without this change and verifying that BDT score histograms are identical.

This merge request affects 1 package:

• Event/xAOD/xAODTrigger

This merge request affects 1 file:

• Event/xAOD/xAODTrigger/xAODTrigger/versions/eFexTauRoI_v1.h

Adding @tamartin ,@akraszna as watchers

added EDM L1Calo Tau Trigger analysis-review-required main review-pending-level-1 labels

CI Result SUCCESS (hash b00656d6)

	Athena	AnalysisBase	AthAnalysis
externals
cmake
make
tests

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AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 3338]

The change is straightforward and there are no issues with the CI. Approving from L1.

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

MR does not affect analysis model,. approving from AR side

Giovanni (AR)

removed analysis-review-required label

added analysis-review-approved label

added review-approved-point1 label

merged

mentioned in commit 91e4c798