Blocks: In scan_delimiters extract static method

[jeherve]

Ports 185482-ghe-Automattic/wpcom

Proposed changes:

When scan_delimiters() is attempting to find the end of an HTML
comment, it’s calling a convenience method which is also a closure
in the code (or an anonymous function). This carries a marginal
performance overhead and limits reuse.

In this change that method is extracted onto the class as its own static
method; this should simplify reasoning about the method itself and
provide a perofmrnace lift to the calling code.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

• N/A

Does this pull request change what data or activity we track or use?

• No

Testing instructions:

Functionality should not change, I would consequently recommend checking if the tests still pass.

[github-actions]

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[github-actions]

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Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/packages/block-delimiter/src/class-block-delimiter.php	205/271 (75.65%)	0.01%	-1 💚

Full summary · PHP report · JS report