pgsql: Fix ABI break introduced by commit 4daa140a2f.

Fix ABI break introduced by commit 4daa140a2f.

Move the newly defined enum value REORDER_BUFFER_CHANGE_INTERNAL_SPEC_ABORT
at the end to avoid ABI break in the back branches. We need to back-patch
this till v11 because before that it is already at the end.

Reported-by: Tomas Vondra
Backpatch-through: 11
Discussion: https://postgr.es/m/CAExHW5sPKF-Oovx_qZe4p5oM6Dvof7_P+XgsNAViug15Fm99jA@mail.gmail.com

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/56e366f6757d24b07cc7c2de2e5151dc372d059e

Modified Files
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src/include/replication/reorderbuffer.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)