[7.5] Kibana 7.0.0 URL field formatter doesn't render relative hyperl…

[alexwizp]

Closes: #35235 (one-file fix for 7.5 branch)

Summary

Kibana 7.0.0 URL field formatter doesn't render relative hyperlinks properly

Related to #53265

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• This was checked for cross-browser compatibility, including a check against IE11
• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• This was checked for keyboard-only and screenreader accessibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately
• This includes a feature addition or change that requires a release note and was labeled appropriately

[elasticmachine]

Pinging @elastic/kibana-app-arch (Team:AppArch)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: b356371

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[alexwizp]

@elasticmachine merge upstream

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 52eaded

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[streamich]

Code LGTM.