Limit http.send in rego evaluation to "normal" public IPs.

[evankanderson]

Summary

Use a new feature in OPA v1.0.0 to patch the HTTP roundtripper to only send to public IP addresses.

Change Type

Mark the type of change your PR introduces:

• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

Manual testing and then added unit tests, then figured out what raise_error actually does in http.send: open-policy-agent/opa#5805 (hint: it doesn't fail the whole rule and return an error, it just drops that particular branch of evaluation...)

Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[blkt]

LGTM, although linter is yelling.