pgsql: Update .abi-compliance-history for change to TransitionCaptureSt

Update .abi-compliance-history for change to TransitionCaptureState.

As noted in the commit message for b4307ae2e54, the change to the
TransitionCaptureState structure is nominally an ABI break, but it is
not expected to affect any third-party code. Therefore, add it to the
.abi-compliance-history file.

Discussion: https://postgr.es/m/19380-4e293be2b4007248%40postgresql.org
Backpatch-through: 15-18

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b06e7c10d17276c1aecc06d4267e2663bcb3689c

Modified Files
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.abi-compliance-history | 11 +++++++++++
1 file changed, 11 insertions(+)