pgsql: psql: do file completion for \gx

psql: do file completion for \gx

This was missed when the feature was added.

Reported-by: Vik Fearing

Discussion: /messages/by-id/eca20529-0b06-b493-ee38-f071a75dcd5b@postgresfriends.org

Backpatch-through: 10

Branch
------
REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a936012d6b2c9b05b856b3fc936fb2ac6af09164

Modified Files
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src/bin/psql/tab-complete.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)