fix: warnings for short imports should not be shown for minified code

[rosen-vladimirov]

In some cases when there's minified code, CLI prints warning for short imports, while in fact there's no such thing in the code.
Fix the regular exepression to be more strict.
Also, instead of iterrating over each regular expression for core-modules directories, join them in a single RegExp. This improves the worst case scenario (i.e. when there are short imports for xml of tns-core-modules) with around 40%.

PR Checklist

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What is the current behavior?

CLI prints warnings for short imports when there's require and text/javascript on one line.

What is the new behavior?

CLI prints warnings only for actual requires.

Fixes issue #4458