feat(grafana): Introduce profiling container port

In order to enable profiling using Grafana Alloy and Grafana Pyroscope
currently you would need to abuse another container port or insert a
dummy container to facitilitate profile collection.

This is because a containerPort is matched with the annotations to
enable profiling. As a workaround I am "abusing" the port :9094, as for
the example I am working on it is unused. This change will make it
possible to coexist with gossip-tcp and you would be able to enable
profiling like this:

```
helm upgrade -n pyroscope-test --install grafana grafana/grafana \
  --set env.GF_DIAGNOSTICS_PROFILING_ENABLED=true \
  --set env.GF_DIAGNOSTICS_PROFILING_ADDR=0.0.0.0 \
  --set env.GF_DIAGNOSTICS_PROFILING_PORT=6060 \
  --set-string 'podAnnotations.profiles\.grafana\.com/cpu\.scrape=true' \
  --set-string 'podAnnotations.profiles\.grafana\.com/cpu\.port=6060' \
  --set-string 'podAnnotations.profiles\.grafana\.com/memory\.scrape=true' \
  --set-string 'podAnnotations.profiles\.grafana\.com/memory\.port=6060' \
  --set-string 'podAnnotations.profiles\.grafana\.com/goroutine\.scrape=true' \
  --set-string 'podAnnotations.profiles\.grafana\.com/goroutine\.port=6060'
```

This is realted to grafana/pyroscope#3753

Signed-off-by: Christian Simon <[email protected]>

charts/grafana/templates/_pod.tpl

@@ -1088,6 +1088,9 @@ containers:
       - name: {{ .Values.gossipPortName }}-udp
         containerPort: 9094
         protocol: UDP
+      - name: profiling
+        containerPort: 6060
+        protocol: TCP
     env:
       - name: POD_IP
         valueFrom: