Fix ingress does not contain a valid IngressClass

Add the ingressClassName field  if the k8s version higher then 1.19-0.

See: https://kubernetes.github.io/ingress-nginx/#what-is-an-ingressclass-and-why-is-it-important-for-users-of-ingress-nginx-controller-now

Author: beshkenadze

charts/meilisearch/templates/ingress.yaml

@@ -25,6 +25,9 @@ metadata:
   {{- . | toYaml | nindent 4 }}
   {{- end }}
 spec:
+  {{- if semverCompare ">=1.19-0" .Capabilities.KubeVersion.GitVersion -}}
+  ingressClassName: nginx
+  {{- end }}
   {{- if .Values.ingress.tls }}
   tls:
     {{- range .Values.ingress.tls }}