Several typo corrections in core files inline documents

[shailu25]

Several typo corrections in core files inline documents

1. In wp-includes/Text/Diff.php Line 299

case-insensitve

It should be

case-insensitive

2. In wp-includes/class-wp-customize-widgets.php Line 826 & 1311

JSON-serializeable

It should be

JSON-serializable

3. In wp-includes/global-styles-and-settings.php Line 57

behaviour

It should be

behavior

[shailu25]

Patch Added

[shailu25]

Updated Patch

[shailu25]

I have added behavior by mistake, but not able to remove/edit in ticket description

Updated patch accordingly

[sabernhardt]

The handbook says to use ​American spelling, so "behavior" is correct in the first patch, 60285.patch​.

Also, Text_Diff is an external dependency, but it's no longer maintained (#59580). Correcting the typo is probably fine in this ticket.

Commits that introduced typos to Core:

• [7747] added Text_Diff
• [27419] added the Widget Customizer
• [55155] added "behaviour" in wp_get_global_settings()

[SergeyBiryukov]

In 57309:

Docs: Fix several typos in inline comments.

Follow-up to [7747], [27419], [55155].

Props shailu25, sabernhardt.
Fixes #60285.