Tweak - Declare WordPress 7.0 Compatibility

[Abdalsalaam]

Related Issue(s)

• Fixes WOOTAX-291

Description

Declares compatibility with WordPress 7.0:

• Bumps Tested up to from 6.9 to 7.0
• Bumps Requires at least from 6.8 to 6.9
• Adds a 3.6.3 changelog entry in both changelog.txt and readme.txt

Testing Instructions

1. Check out this branch on your local environment.
2. On a site running WordPress 7.0, activate WooCommerce Tax and confirm the plugin loads with no errors/warnings.
3. Smoke test core flows (tax calculation, settings page) to confirm no regressions.
4. In the plugin header (woocommerce-services.php) and readme.txt, verify Tested up to: 7.0 and Requires at least: 6.9.
5. Verify the 3.6.3 entry appears in both changelog.txt and the Changelog section of readme.txt.

Screenshots (if applicable):

N/A — header/changelog metadata only, no visual changes.

Types of changes:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore, refactoring or updating dependencies (code change that does not change functionality)

Checklist:

• My code follows the WordPress Coding Standards and Security Best Practices.
• My change requires an update to our documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• I have added a changelog.txt entry.
• I have added a changelog entry to the readme.txt file.
• My PR doesn't impact Woo mobile apps, OR I've tested and confirmed it works fine on Woo mobile (if it impacts mobile, add the impacts-woo-mobile label)