Add ECK 2.11

[naemono]

This adds the ECK 2.11 branch to the build list. ECK 2.11.0 is planned for release on January 9th.

[github-actions]

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[kilfoyle]

LGTM! 🚀

[naemono]

@elastic/docs-repo-owners Since the 2.11/8.12 release is tomorrow, I'm needing to merge this PR today. Could someone with write access handle that for me please? Thanks much!

[kilfoyle]

buildkite test this rebuild

[kilfoyle]

run docs-build

[kilfoyle]

Closing and re-opening to relaunch CI checks.

[kilfoyle]

@elasticmachine run docs-build

[kilfoyle]

@elasticmachine run elasticsearch-ci/docs

[naemono]

Thanks @kilfoyle , that wasn't simple. 😬

[kilfoyle]

My pleasure @naemono! I was a little confused about those CI checks but I'm glad everything is green and merged. :-)