fix: avoid source map plugin from replacing valid code

[JonathanWbn]

• Closes Sourcemap plugin breaks JS files #30889

Additional details

The regex condition to find source map links would catch code that wasn't actually a source map link, but only looked like it.

A real source map link would always look like this: //# sourceMappingURL=a-real-file-path.js

So I decided to refine the regex to ensure it doesn't match if there is a ' or " after the =. Because valid source map URL's won't have these quotes, but these edge cases where this snippet is part of the code will have it.

Steps to test

The broken behaviour can be reproduced by importing a JS file that looks like a source map link, but isn't actually one, e.g.:

console.log("//# sourceMappingURL=")

How has the user experience changed?

There are no changes to the user experience, but some edge cases that previously would break will no longer break.

PR Tasks

• Have tests been added/updated?
• Has a PR for user-facing changes been opened in cypress-documentation?
• Have API changes been updated in the type definitions?

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[jennifer-shehane]

@JonathanWbn Thanks for the contribution! Could you please sign our CLA?

[jennifer-shehane]

Rerunning since I think those failures may have been 14.0 related