[DOCS] Remove /next reference from already published doc versions

[bhasudha]

Change Logs

Docs clean up. No new changes. Remove all references to /docs/next/... and replace with /docs/... for links sanity. Otherwise some older versions were pointing to /docs/next/... paths.

Impact

website hygiene

Risk level (write none, low medium or high below)

Low

Documentation Update

Describe any necessary documentation update if there is any new feature, config, or user-facing change

• The config description must be updated if new configs are added or the default value of the configs are changed
• Any new feature or user-facing change requires updating the Hudi website. Please create a Jira ticket, attach the
  ticket number here and follow the instruction to make
  changes to the website.

Contributor's checklist

• Read through contributor's guide
• Change Logs and Impact were stated clearly
• Adequate tests were added if applicable
• CI passed

[nsivabalan]

is this tested and the links are good?

[bhasudha]

is this tested and the links are good?

Yes. tested locally. looks okay. Waiting for CI to see if there are any other broken links.