feat: add security context for ingress container (#564)

Co-authored-by: Katlinsky, Ilya <i.katlinsky@itransition.com>
diff --git a/charts/apisix-ingress-controller/templates/deployment.yaml b/charts/apisix-ingress-controller/templates/deployment.yaml
index ba73b48..df0337d 100644
--- a/charts/apisix-ingress-controller/templates/deployment.yaml
+++ b/charts/apisix-ingress-controller/templates/deployment.yaml
@@ -75,6 +75,8 @@
             - ingress
             - --config-path
             - /ingress-apisix/conf/config.yaml
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
           image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
           imagePullPolicy: {{ .Values.image.pullPolicy }}
           ports: