Update to new release API endpoints

[navyau09]

Release API migration to new endpoints is now complete.

Past Release Endpoint : https://elastic-release-api.s3.us-west-2.amazonaws.com/public/past-releases.json
Future Release Endpoint : https://elastic-release-api.s3.us-west-2.amazonaws.com/public/future-releases.json

This PR updates the old Release API endpoints to new one's

More Info:
https://groups.google.com/a/elastic.co/g/release-eng-team/c/qgXaCX-y29k/m/jzm2S8MeAwAJ

[mergify]

This pull request does not have a backport label. Could you fix it @navyau09? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 8./d branch. /d is the digit
• backport-active-all is the label that automatically backports to all active branches.
• backport-active-8 is the label that automatically backports to all active minor branches for the 8 major.
• backport-active-9 is the label that automatically backports to all active minor branches for the 9 major.