Remove symbols statefulset (#4469)

Starting in Sourcegraph 6.4, the Symbols and Searcher services are now
combined, for easier operation, simplified architecture, and better
resource utilization.

Customers can delete the service if not deleted automatically, and may
want to consider reallocating resources previously given to symbols to
searcher. Environment variables should be copied over from symbols to
searcher.

Test plan: This deployment ran for ~2 weeks on S2 and dotcom already and
has signoff from team-product-platform.

### Checklist

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- [ ]
[CHANGELOG.md](https://github.com/sourcegraph/sourcegraph/blob/main/CHANGELOG.md)
updated
- [x] [K8s Upgrade notes
updated](https://github.com/sourcegraph/sourcegraph/blob/main/doc/admin/updates/kubernetes.md)
- [x] Sister
[deploy-sourcegraph-k8s](https://github.com/sourcegraph/deploy-sourcegraph-docker)
change:
- [x] Sister
[deploy-sourcegraph-docker](https://github.com/sourcegraph/deploy-sourcegraph-docker)
change:
- [x] All images have a valid tag and SHA256 sum
- [x] I acknowledge that
[deploy-sourcegraph-k8s](https://github.com/sourcegraph/deploy-sourcegraph-k8s)
is now the preferred Kubernetes deployment repository

Author: eseliger

base/symbols/symbols.Deployment.yaml

@@ -22,8 +22,6 @@ resources:
 - base/grafana/grafana.ServiceAccount.yaml
 - base/syntect-server/syntect-server.Service.yaml
 - base/syntect-server/syntect-server.Deployment.yaml
-- base/symbols/symbols.Service.yaml
-- base/symbols/symbols.Deployment.yaml
 - base/pgsql/pgsql.ConfigMap.yaml
 - base/pgsql/pgsql.Service.yaml
 - base/pgsql/pgsql.Deployment.yaml

base/symbols/symbols.Service.yaml

@@ -74,12 +74,6 @@ patches:
     group: apps
     version: v1
   path: delete-resources.yaml
-- target:
-    kind: Deployment
-    name: symbols
-    group: apps
-    version: v1
-  path: delete-resources.yaml
 - target:
     kind: Deployment
     name: syntect-server

overlays/bases/deployments/kustomization.yaml

@@ -74,12 +74,6 @@ patches:
       group: apps
       version: v1
     path: delete-resources.yaml
-  - target:
-      kind: Deployment
-      name: symbols
-      group: apps
-      version: v1
-    path: delete-resources.yaml
   - target:
       kind: Deployment
       name: syntect-server

overlays/low-resource/kustomization.yaml

@@ -22,5 +22,4 @@ patchesStrategicMerge:
   - redis/redis-store.Deployment.yaml
   - worker/worker.Deployment.yaml
   - searcher/searcher.Deployment.yaml
-  - symbols/symbols.Deployment.yaml
   - syntect-server/syntect-server.Deployment.yaml

overlays/minikube/kustomization.yaml

@@ -327,26 +327,6 @@ metadata:
 ---
 apiVersion: apps/v1
 kind: Deployment
-metadata:
-  name: symbols
-# spec:
-#   replicas: 1
-#   template:
-#     spec:
-#       containers:
-#       - name: symbols
-#         resources:
-#           limits:
-#             cpu: "2"
-#             ephemeral-storage: "12G"
-#             memory: 2G
-#           requests:
-#             cpu: 500m
-#             ephemeral-storage: "10G"
-#             memory: 500M
----
-apiVersion: apps/v1
-kind: Deployment
 metadata:
   name: syntect-server
 # spec: