fix: incorrect condiional check in Gutenberg_Token_Map_6_7::read_small_token()

[justlevine]

What?

This PR fixes an issue in Gutenberg_Token_Map_6_7::read_small_token() where a misplaced ) results in a strtoupper( {... text check logic ... }, causing the conditional to incorrectly handle case-insensitive checks.

Why?

While this issue was surfaced by PHPStan (via #66693) it can be remediated independently as part of #66598

How?

Testing Instructions

Testing Instructions for Keyboard

Screenshots or screencast

Before	After

[github-actions]

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Co-authored-by: justlevine <justlevine@git.wordpress.org>
Co-authored-by: carolinan <poena@git.wordpress.org>

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[carolinan]

This line is also present in https://github.com/WordPress/wordpress-develop/blob/trunk/src/wp-includes/class-wp-token-map.php#L610

[Mamaduka]

Hi, @justlevine

Now that we have removed WP 6.7 compat from the plugin (#70023). This patch needs to be submitted to the core repo.

I'm going to close this PR. Thanks again, @justlevine!