pgsql: Remove unnecessary includes of <signal.h>

Remove unnecessary includes of <signal.h>

These were once needed for sig_atomic_t, but that no longer appears in
these headers, so the include is not needed.

Reviewed-by: Shubham Khanna <Shubham.Khanna@fujitsu.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: /messages/by-id/cff5475d-e0a9-4561-b094-794aa36bd031@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dffb2b478f54f4abdd0271bbab44d3f81d017648

Modified Files
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src/include/replication/walsender.h | 2 --
src/include/replication/worker_internal.h | 2 --
2 files changed, 4 deletions(-)