fix: omit protocol does not require pre-transform

[XiSenao]

Description

fix: #15335

Additional context

From a logical standpoint, it appears that at this stage, only JS requests or CSS requests are invoked with preTransformRequest, which is generally expected. However, when calling preTransformRequest from processNodeUrl, we may need to prevent the parsing of external JS or CSS request links. Therefore, this modification filters potential external links starting with //.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[sapphi-red]

Actually I think we should only call preTransformRequest for module script tag links instead. It seems we are calling it for classic script tag links and non-script tag links (e.g. img tags).

[XiSenao]

From a logical standpoint, it appears that at this stage, only JS requests or CSS requests are invoked with preTransformRequest, which is generally expected. However, when calling preTransformRequest from processNodeUrl, we may need to prevent the parsing of external JS or CSS request links.

[sapphi-red]

Ah, I missed the shouldPreTransform call.

[patak-dev]

Nice! Thanks for the fix