Assign "Identifier" attribute to opening double quote instead of "Comment"

Summary:
When the PostgreSQL syntax definition file was converted from using named attributes and contexts instead of numbers in [this commit](https://invent.kde.org/kde/kate/-/commit/2e55bd0ca7deaaffe5546f04e2925112cca2a9a6#5d04d3f12b2774e3618e339c318f3154ac45df03), the attribute for an opening double quote was incorrectly set to `"Comment"` instead of `"Identifier"`. This patch fixes that.

BUG: 421445

Test Plan:
Incorrect opening double quote before fix:

{F8318517}

Correct opening double quote after fix:

{F8318530}

Reviewers: #framework_syntax_highlighting, dhaumann

Reviewed By: #framework_syntax_highlighting, dhaumann

Subscribers: cullmann, dhaumann, kwrite-devel, kde-frameworks-devel

Tags: #framework_syntax_highlighting, #kate, #frameworks

Differential Revision: https://phabricator.kde.org/D29735