Make sure Git resources are released before git_libgit2_shutdown

It may happen (in some error condition) that finalize() is skipped, in which case the Git resources might not be released before ~GitEntityResolver, so it's important to ensure they are released to avoid a segfault.

The problem was exposed by gaudi/Gaudi!1432 (merged) because it changed the failure mode of a couple of tests in XMLSummaryKernel (see !4023 (merged)) and the new failure mode hit the corner case I'm fixing here.

/cc @sponce

/ci-test

added RTA label

added ci-test-triggered label

• [2023-03-23 10:18] Validation started with lhcb-master-mr#7416

mentioned in merge request Run2Support!39 (merged)

resolved all threads

added backport run2 ~41915 labels

approved this merge request

merged

mentioned in commit 840dd648

mentioned in merge request !4034 (merged)

Backported to run2-patches in !4034 (merged)

removed backport run2 label

mentioned in merge request !4035 (merged)

mentioned in merge request !4048

Backported to sim10-patches in !4048