Fix Post Date Block: Semantic use of date tag inside link

[aliaghdam]

What?

In the Post Date block PHP render function the post link tag is wrapped by time tag that is not correct semantically because the time tag should not inlclude interactive element. Also in the block JS render function it works correctly by wrapping the time tag by the link tag.

Testing Instructions

1. Open a post or page.
2. Insert a Post Date block.
3. Save and check the front end.

Screenshots

Before	After

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

If you're merging code through a pull request on GitHub, copy and paste the following into the bottom of the merge commit message.

Co-authored-by: aliaghdam <aliaghdam@git.wordpress.org>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

[github-actions]

Warning: Type of PR label mismatch

To merge this PR, it requires exactly 1 label indicating the type of PR. Other labels are optional and not being checked here.

• Required label: Any label starting with [Type].
• Labels found: .

Read more about Type labels in Gutenberg. Don't worry if you don't have the required permissions to add labels; the PR reviewer should be able to help with the task.