fix: explicitly specify TCP protocol for helm SSA compatibility (#692) (#1901)

**Description of the change**
This PR adds the explicit `protocol: TCP` field to the port definitions
in the Sealed Secrets Helm chart.

While TCP is the default protocol in Kubernetes, Server-Side Apply (SSA)
on clusters running version 1.19 or earlier can reject manifests if the
protocol is not explicitly defined. This change ensures the Helm chart
is compatible with modern GitOps workflows (like ArgoCD or Flux using
SSA) across all supported Kubernetes versions.

**Targeted Files:**
- `templates/deployment.yaml`: Added `protocol: TCP` to the http and
metrics container ports.
- `templates/service.yaml`: Added `protocol: TCP` to the main service
and metrics service port definitions.

**Benefits**
- Resolves deployment failures when using Server-Side Apply on older
Kubernetes clusters (<= 1.19).
- Improves manifest explicitness and follows best practices for
cross-version compatibility.

**Applicable issues**
- fixes #692

**Checklist**
- [x] I have read the CONTRIBUTING doc.
- [x] My commit is Signed-off-by using `git commit -s`.
- [ ] (If applicable) Table of Contents in `README.md` or `values.txt`
has been updated via `doctoc`.
- [x] Changes are focused solely on the Helm YAML templates as
requested.

Signed-off-by: Emmanuel Tom Jose <84658038+leantos@users.noreply.github.com>

Author: leantos

helm/sealed-secrets/templates/deployment.yaml

@@ -181,13 +181,15 @@ spec:
           ports:
             - name: http
               containerPort: {{ .Values.containerPorts.http | default "8080" }}
+              protocol: TCP
               {{- if .Values.hostNetwork }}
               hostPort: {{ .Values.containerPorts.http }}
               {{- else if .Values.hostPorts.http }}
               hostPort: {{ .Values.hostPorts.http }}
               {{- end }}
             - name: metrics
               containerPort: {{ .Values.containerPorts.metrics | default "8081" }}
+              protocol: TCP
               {{- if .Values.hostNetwork }}
               hostPort: {{ .Values.containerPorts.metrics }}
               {{- else if .Values.hostPorts.metrics }}

helm/sealed-secrets/templates/service.yaml

@@ -29,6 +29,7 @@ spec:
     - name: http
       port: {{ .Values.service.port }}
       targetPort: http
+      protocol: TCP
       {{- if and (or (eq .Values.service.type "NodePort") (eq .Values.service.type "LoadBalancer")) (not (empty .Values.service.nodePort)) }}
       nodePort: {{ .Values.service.nodePort }}
       {{- else if eq .Values.service.type "ClusterIP" }}
@@ -67,6 +68,7 @@ spec:
     - name: metrics
       port: {{ .Values.metrics.service.port }}
       targetPort: metrics
+      protocol: TCP
       {{- if and (or (eq .Values.metrics.service.type "NodePort") (eq .Values.metrics.service.type "LoadBalancer")) (not (empty .Values.metrics.service.nodePort)) }}
       nodePort: {{ .Values.metrics.service.nodePort }}
       {{- else if eq .Values.metrics.service.type "ClusterIP" }}