Backport of added redirect for conf entries 1.8.x into release/1.12.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #19460 to be assessed for backporting due to the inclusion of the label backport/1.12.

The below text is copied from the body of the original PR.

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Description

Prior to v1.9.x, configuration entries appeared int he /agent dir instead the /connect dir. This PR redirects people who view a conf entry in the current /connect folder and switch to docs v1.8.x so that they land on the conf entry in the /agent folder. Fixes per this Slack thread.

PR Checklist

• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 21f193c

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

[hc-github-team-consul-core]

🤔 This PR has changes in the website/ directory but does not have a type/docs-cherrypick label. If the changes are for the next version, this can be ignored. If they are updates to current docs, attach the label to auto cherrypick to the stable-website branch after merging.

[hc-github-team-consul-core]

🤔 This PR has changes in the website/ directory but does not have a type/docs-cherrypick label. If the changes are for the next version, this can be ignored. If they are updates to current docs, attach the label to auto cherrypick to the stable-website branch after merging.

[hc-github-team-consul-core]

🤔 This PR has changes in the website/ directory but does not have a type/docs-cherrypick label. If the changes are for the next version, this can be ignored. If they are updates to current docs, attach the label to auto cherrypick to the stable-website branch after merging.

[trujillo-adam]

Will manually backport instead