chore(deps)!: Migrate to Valkey from Redis (#775)

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### Description of the change

Migrates from Redis to Valkey.

### Benefits

The Redis License is changing from BSD-3-Clause to RSALv2 and SSPLv1 which are not open source under the OSI definition. We should consider open-source alternatives as a default replacement for Redis.

### Possible drawbacks

Large scale change, potentially breaking.

### Applicable issues

https://github.com/go-gitea/gitea/issues/32056

### ⚠ BREAKING

Major version change, redis provider changed to valkey.

### Checklist

<!-- [Place an '[X]' (no spaces) in all applicable fields. Please remove unrelated fields.] -->

- [X] Parameters are documented in the `values.yaml` and added to the `README.md` using [readme-generator-for-helm](https://github.com/bitnami-labs/readme-generator-for-helm)
- [X] Breaking changes are documented in the `README.md`
- [X] Helm templating unittests are added (required when changing anything in `templates` folder)

Co-authored-by: pat-s <patrick.schratz@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-gitea/pulls/775
Reviewed-by: pat-s <pat-s@noreply.gitea.com>
Co-authored-by: Sean Teo <sawntoe@gmail.com>
Co-committed-by: Sean Teo <sawntoe@gmail.com>

values.yaml

@@ -509,41 +509,51 @@ gitea:
     successThreshold: 1
     failureThreshold: 10
 
-## @section redis-cluster
-## @param redis-cluster.enabled Enable redis cluster
-# ⚠️ The redis charts do not work well with special characters in the password (<https://gitea.com/gitea/helm-gitea/issues/690>).
+## @section valkey-cluster
+## @param valkey-cluster.enabled Enable valkey cluster
+# ⚠️ The valkey charts do not work well with special characters in the password (<https://gitea.com/gitea/helm-chart/issues/690>).
 # Consider omitting such or open an issue in the Bitnami repo and let us know once this got fixed.
-## @param redis-cluster.usePassword Whether to use password authentication
-## @param redis-cluster.cluster.nodes Number of redis cluster master nodes
-## @param redis-cluster.cluster.replicas Number of redis cluster master node replicas
+## @param valkey-cluster.usePassword Whether to use password authentication
+## @param valkey-cluster.usePasswordFiles Whether to mount passwords as files instead of environment variables
+## @param valkey-cluster.cluster.nodes Number of valkey cluster master nodes
+## @param valkey-cluster.cluster.replicas Number of valkey cluster master node replicas
+## @param valkey-cluster.service.ports.valkey Port of Valkey service
 ## @descriptionStart
-## Redis cluster and [Redis](#redis) cannot be enabled at the same time.
+## Valkey cluster and [Valkey](#valkey) cannot be enabled at the same time.
 ## @descriptionEnd
-redis-cluster:
+valkey-cluster:
   enabled: true
   usePassword: false
+  usePasswordFiles: false
   cluster:
     nodes: 3 # default: 6
     replicas: 0 # default: 1
+  service:
+    ports:
+      valkey: 6379
 
-## @section redis
-## @param redis.enabled Enable redis standalone or replicated
-## @param redis.architecture Whether to use standalone or replication
-# ⚠️ The redis charts do not work well with special characters in the password (<https://gitea.com/gitea/helm-gitea/issues/690>).
+## @section valkey
+## @param valkey.enabled Enable valkey standalone or replicated
+## @param valkey.architecture Whether to use standalone or replication
+# ⚠️ The valkey charts do not work well with special characters in the password (<https://gitea.com/gitea/helm-chart/issues/690>).
 # Consider omitting such or open an issue in the Bitnami repo and let us know once this got fixed.
-## @param redis.global.redis.password Required password
-## @param redis.master.count Number of Redis master instances to deploy
+## @param valkey.global.valkey.password Required password
+## @param valkey.master.count Number of Valkey master instances to deploy
+## @param valkey.master.service.ports.valkey Port of Valkey service
 ## @descriptionStart
-## Redis and [Redis cluster](#redis-cluster) cannot be enabled at the same time.
+## Valkey and [Valkey cluster](#valkey-cluster) cannot be enabled at the same time.
 ## @descriptionEnd
-redis:
+valkey:
   enabled: false
   architecture: standalone
   global:
-    redis:
+    valkey:
       password: changeme
   master:
     count: 1
+    service:
+      ports:
+        valkey: 6379
 
 ## @section PostgreSQL HA
 #