pgsql: Fix potential buffer overruns in proto.c.

Fix potential buffer overruns in proto.c.

Prevent potential buffer overruns when using strcpy to gid buffer. This
has been introduced by commit a8fd13cab0.

Reported-by: Tom Lane as per coverity
Author: Peter Smith
Reviewed-by: Amit Kapila
Discussion: https://www.postgresql.org/message-id/161029.1626639923%40sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/01c3adcdd85f1507ef49bdf5430c59925d08de6f

Modified Files
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src/backend/replication/logical/proto.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)