Cache `GroovySourceFileAllowlist` responses and remove entries from the default allowlist that are unrelated to `WithScriptDescriptor.WithScriptAllowlist`

[dwnusbaum]

See https://github.com/jenkinsci/workflow-cps-plugin/pull/538#issuecomment-1883442531.

GroovySourceFileAllowlist can be consulted many times, but the allowed files are effectively static and just depend on which plugins are installed. Once a file has been allowed once, we don't need to check all of the allowlists again.

Testing done

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