Update ES clients to use stackcurrent and stacklivemain variables

[jrodewig]

Updates the following ES clients docs to use the stackcurrent and stacklivemain variables:

• Java
• JavaScript
• Ruby
• Go
• .NET
• PHP
• Python

This will bump the current branch for these docs to 8.0. It'll also ensure the clients stay synced with stack releases in the future.

This does not update the current version for the Perl or Rust clients.

[philkra]

LGTM -- I double checked the repos and the branches are in place. Thanks James for opening the PR

[jrodewig]

This change is causing some links from the legacy elasticsearch.js docs to the ES JS client docs to break. To fix those links, I've opened elastic/elasticsearch-js#1634 to add some related redirects. I've also reached out to the clients team about updating the legacy docs.

We should also investigate whether we can use the stackcurrent and stacklivemain variables for these client docs instead of hardcoding the current and live branches. I'll reach out to the clients team about this on Monday.

[jrodewig]

I spoke with @philkra and confirmed that we can use the stackcurrent and stacklivemain variables.

I'll merge this in once elastic/elasticsearch-js#1634 is merged and backported.

[philkra]

Thanks @jrodewig , the PR elastic/elasticsearch-js#1634 is merged on main

[gtback]

@elasticmachine run elasticsearch-ci/docs

[gtback]

LGTM once the builds pass.

[jrodewig]

@elasticmachine run elasticsearch-ci/docs