Enhancement: Add Footer Template Part

[masteradhoc]

Describe the bug

See #6197

Changes in the PR

Footer template part that on all woo pages uses now <footer class="wp-block-template-part"> instead of <div class="wp-block-template-part">.

Header template part that on woo pages uses now <header class="wp-block-template-part"> instead of <div class="wp-block-template-part">.

Fixes #6197

Screenshots

Before:

After:

User Facing Testing

1. Go to a Woo page and view the source.
2. Check the header is wrapped in a <header> tag, not in a <div>.
3. Check the footer is wrapped in a <footer> tag, not in <div>.

WooCommerce Visibility

no visible changes in this PR

Performance Impact

no Performance Impacts

Changelog

Enhancement: Footer Template Parts use now <footer> instead of <div> and Header uses <header> instead of <div>.

[albarin]

Hey @masteradhoc, thanks a lot for your contribution!
Would be really helpful for us if you could complete the PR description according to the PR template. Feel free to delete the sections that don't apply to your changes. Please let us know if you have any doubts or if we can help you with something.
Thanks again! 😄