Use regex for gutterInjection line splitting

[bogdancondorachi]

Hi there @brendt, as mentioned on #104 I have a specific scenario where gutterInjection shows only on the first line (all other cases work as expected). It seems like the issue is the way you line splitting the content using explode(PHP_EOL, $content) as it has limited flexibility when handling all line break conventions correctly.

Given this I've switched to preg_split('/\R/', trim($content)) which offers more versatility and flexibility, solving my specific scenario. From my testing, it should work in most environments and be a more reliable solution.

[brendt]

Makes sense, thanks for sending the PR 👍

[brendt]

Released: https://github.com/tempestphp/highlight/releases/tag/2.3.5

[coveralls]

Pull Request Test Coverage Report for Build 8999646164

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Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 95.285%

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Totals
Change from base Build 8920957065:	0.0%
Covered Lines:	1455
Relevant Lines:	1527

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💛 - Coveralls