Fix support to read EPP plugin config to be read from yaml

Author: rahulgurnani

config/charts/inferencepool/templates/epp-config.yaml

@@ -20,4 +20,7 @@ data:
   {{- if (hasKey .Values.inferenceExtension "pluginsCustomConfig") }}
   {{- .Values.inferenceExtension.pluginsCustomConfig | toYaml | nindent 2 }}
   {{- end }}
+  {{- if (hasKey .Values.inferenceExtension "pluginsConfigFile")}}
+    {{- .Files.Get (printf "%s" .Values.inferenceExtension.pluginsConfigFile) | indent 4}}
+  {{- end}}