Allow namespace configuration for different CRD resources in Fission (#2539)

* Allow multiple namespaces for builder manager
* Enable multiple namespaces for executor informers
* Added missing context
* helm chart support for multiple namespaces
* Directly consume map type from GetInformerForNamespaces fn
* Optimize function resolver by choosing namespace-specific informer
* helm chart support for multiple namespaces
* consider default namespace and move duplicate code to helm template
* Improve documentation for fission namespace values

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>
Co-authored-by: shubham bansal <shubhambansaliimtgn@gmail.com>

charts/fission-all/templates/_helpers.tpl

@@ -71,3 +71,12 @@ This template generates the image name for the deployment depending on the value
 - name: OTEL_PROPAGATORS
   value: "{{ .Values.openTelemetry.propagators }}"
 {{- end }}
+
+{{- define "fission-resource-namespace.envs" }}
+- name: FISSION_RESOURCE_NAMESPACES
+{{- if not .Values.singleDefaultNamespace }}
+  value: "{{ .Values.defaultNamespace }},{{ join "," .Values.additionalFissionNamespaces }}"
+{{- else }}
+  value: {{ .Values.defaultNamespace }}  
+{{- end }}
+{{- end }}