pgsql: Fix busted tab completion of extension versions.

Fix busted tab completion of extension versions.

In 02b8048ba I (tgl) got rid of the need for most tab-completion queries
to return pre-quoted identifiers. But I over-hastily removed the
quote_ident call from Query_for_list_of_available_extension_versions*
too; those still need it, because what is returned isn't an identifier
at all and will (almost?) always need quoting.

Arguably we should use quote_literal here instead. But quote_ident
works too and people may be used to that behavior, so stick with it.

In passing, fix inconsistent omission of schema-qualification in
Query_for_list_of_encodings. That's not a security issue per our
current guidelines, but it ought to be like the rest.

Jeff Janes

Discussion: https://postgr.es/m/CAMkU=1yV+egSYrzWvbDY8VZ6bKEMrKbzxr-HTuiHi+wDgSUMgA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9cd43f6cbd8b6fbac6837bcdba5e12f0ecbafefb

Modified Files
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src/bin/psql/tab-complete.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)