perf: cache load plugin

[sapphi-red]

Description

It seems node calls importModuleDynamicallyCallback everytime import is called.
By caching this call, it reduced the start up time of https://github.com/sapphi-red/performance-compare from ~5100ms to ~4700ms.

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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