AthenaKernel: C++20 fixes for DsoDb

Fix build failure with C++20.

I am fixing this deliberately also in 23.0 since that's where the bug got introduced by !64255 (merged).

This merge request affects 1 package:

• Control/AthenaKernel

This merge request affects 1 file:

• Control/AthenaKernel/src/DsoDb.cxx

Adding @gemmeren ,@ssnyder ,@maszyman as watchers

added 23.0 Core review-pending-level-1 labels

changed the description

removed 23.0 Core review-pending-level-1 labels

mentioned in merge request !64255 (merged)

added urgent label

added 23.0 Core review-pending-level-1 labels

CI Result SUCCESS (hash e3f69f00)

	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-CC7 74672]

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

added review-approved-tier0 label

mentioned in commit 18c57b77

merged

picked the changes into the branch cherry-pick-18c57b77 with commit 3c7fee41

mentioned in commit 3c7fee41

mentioned in merge request !64427 (merged)

mentioned in merge request !64457 (merged)