What this PR does / why we need it:
Ban escape matched string on gsql tab-completion.
Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #
It's a gsql tab-complete bug. Type create tex and press TAB, it will be create text\ search. Cause Space is escaped out of expected.
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Release note: