[Serverless nav] Remove trailing forward slash in Cloud URLs

[sebelga]

This PR fixes broken navigation in Cloud UI when navigating there from a serverless project.

I've decided to not change the current URLs being injected in Kibana as a measure of precaution in cases those are used somewhere (expecting the trailing "/"). Instead I parse the URLs that that are then used as href attributes.

Fixes #170475

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[eokoneyo]

Code changes looks good and resolves issue

[sebelga]

Thanks for the review @eokoneyo !

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: 8bc3645

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
securitySolutionServerless	336.6KB	336.8KB	+253.0B

Public APIs missing exports

Total count of every type that is part of your API that should be exported but is not. This will cause broken links in the API documentation system. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats exports for more detailed information.

id	before	after	diff
@kbn/shared-ux-chrome-navigation	4	5	+1

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
serverlessObservability	63.1KB	63.3KB	+253.0B
serverlessSearch	49.5KB	49.8KB	+253.0B
total			+506.0B

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

cc @sebelga