pgsql: Tab-complete CREATE COLLATION.

Tab-complete CREATE COLLATION.

Reviewed-by: Michael Paquier <[hidden email]>
Discussion: https://postgr.es/m/20210117215940.GE8560%40telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5bc09a74719dfeb6c4cebb311b81385c508459a8

Modified Files
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src/bin/psql/tab-complete.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)