chore: Update anyURI to url.URL

[akutz]

Description

This patch updates the existence of anyURI from the WSDL to be a url.URL instead of a string. Please note this is potentially a breaking change and consumers of GoVmomi will need to update any place they expected anyURI to be a string.

Please note we should not yet merge this PR as @dougm highlighted this type was originally url.URL but was changed in #1100. Until we recall why, we do not want to merge this PR.

Closes: NA

Type of change

Please mark options that are relevant:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to
  not work as expected)
• This change requires a documentation update
• Build related change

How Has This Been Tested?

• go build ./...
• go test -v ./vim25/types
• GitHub actions.

Checklist:

• My code follows the CONTRIBUTION guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged

[github-actions]

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inactivity. Mark as fresh by adding the comment /remove-lifecycle stale.