fix: Set a default CODER_ACCESS_URL in Helm (#5041)

* fix: Set a default `CODER_ACCESS_URL` in Helm

This allows for a simple `helm apply` to create a full Coder
deployment that works for creating workspaces.

* Update docs

docs/install/kubernetes.md

@@ -87,8 +87,6 @@ to log in and manage templates.
      # `CODER_TLS_ENABLE`, `CODER_TLS_CERT_FILE` or `CODER_TLS_KEY_FILE` as
      # they are already set by the Helm chart and will cause conflicts.
      env:
-       - name: CODER_ACCESS_URL
-         value: "https://coder.example.com"
        - name: CODER_PG_CONNECTION_URL
          valueFrom:
            secretKeyRef:
@@ -98,6 +96,11 @@ to log in and manage templates.
              name: coder-db-url
              key: url
 
+       # (Optional) For production deployments the access URL should be set.
+       # If you're just trying Coder, access the dashboard via the service IP.
+       - name: CODER_ACCESS_URL
+         value: "https://coder.example.com"
+
        # This env variable controls whether or not to auto-import the
        # "kubernetes" template on first startup. This will not work unless
        # coder.serviceAccount.workspacePerms is true.