pgsql: Fix not-quite-right string comparison in parse_jsonb_index_flags

Fix not-quite-right string comparison in parse_jsonb_index_flags().

This code would accept "strinX", where X is any 1-byte character,
as meaning "string".  Clearly it wasn't meant to do that.

No back-patch, since this doesn't affect correct queries and
there's some tiny chance we'd break somebody's incorrect query
in a minor release.

Report and patch by Dominik Czarnota.

Discussion: https://postgr.es/m/CABEVAa1dU0mDCAfaT8WF2adVXTDsLVJy_izotg6ze_hh-cn8qQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/870ad6a59bbbd95c2dc3cfe67b07d0e079599edf

Modified Files
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src/backend/utils/adt/jsonfuncs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)