Jetpack Modules: Avoid using regexes when possible

[dilirity]

While looking into OOM errors in the modules, I noticed that some checks can benefit from using simple string comparison or str_contains checks.

Proposed changes:

• Use str_contains instead of preg_match;
• Use direct string comparison instead of regexes when possible;
• Reorder string comparisons to be before preg_match checks as they are faster.

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Jetpack product discussion

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[github-actions]

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Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/modules/sitemaps/sitemaps.php	76/218 (34.86%)	-2.03%	0 💚

Full summary · PHP report · JS report

_{Coverage check overridden by I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage. .}

[kraftbj]

Great idea. One suggestion on ordering to have the still-needed preg_matches occur after the simple comparisons have been exhausted.

[kraftbj]

I would imagine it would be more performant to have all of the simple comparisons before any of the preg_matches. Any reason not to have all of them occur before the first preg_match?

[dilirity]

Oh I didn't think of that, thanks for the suggestion!

Updated in 60df508.