Support Implicit Tenant Activation (targeting v1.25.1)

[etiennedi]

To be merged after the RC phase, when the 1.25 GA release is out. Likely to target a patch release, such as 1.25.1.

What's being changed:

• Adds an option (off by default) to allow auto-activation for COLD tenants
• If a read-or-write request comes in and a tenant is COLD, it is automatically activated.
  • UX: The user no longer has to worry about the activity status of a tenant, it becomes fully automatic. They can just query and Weaviate will figure the rest out (comparable to a cache which doesn't fail the request on a cache miss, but rather warms the cache, then proceeds with the request)
  • Under the hood: This activation is passed to the leader, so it does not just update the local state, but rather the global state.
• It is meant to play well with the "Optimistic Tenant Status" design, i.e. if the local node already thinks the tenant is HOT, no leader-query is required. If a leader-query is made and the it still comes back as COLD, we now query the leader again to turn it hot.
  • This could probably be optimized as it now requires two rpc calls, but it works great for now and I didn't want to prematurely optimize this before we see this as a bottleneck.
• There is a new acceptance test that tests the feature in cluster mode both with replication off and on
• Adds some missing unit tests in schema config validation and fixes minor validation bugs

Review checklist

• Documentation has been updated, if necessary. Link to changed documentation:
• Chaos pipeline run or not necessary. Link to pipeline:
• All new code is covered by tests where it is reasonable.
• Performance tests have been run or not necessary.

[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud