add namespace param for fn and env (#2556)

This PR moves fission CLI as closer as possible to kubectl command behaviour.  We have improved namespace handling behaviour across CLI.

* add namespace param for fn and env
* use common fn for ns check
* update validation
* default namespace for httpTrigger, env and package, config and triggers
* use default ns
* add namespace filter to spec
* add forceNamespace flag
* set current namespace
* add default namespace in config
* add namespace specific destroy
* add all namespace in the list of resources
* add namespace as global tag
* use %s instead of %v
* add test cases for namespace
* use ns in get all functions

.github/workflows/push_pr.yaml

@@ -55,7 +55,7 @@ jobs:
         with:
           version: ${{ env.HELM_VERSION }}
 
-      - name: Kind Clutser
+      - name: Kind Cluster
         uses: engineerd/setup-kind@v0.5.0
         with:
           image: kindest/node:${{ matrix.kindversion }}
@@ -67,6 +67,9 @@ jobs:
           kubectl cluster-info --context kind-kind
           kubectl get nodes
           sudo apt-get install -y apache2-utils
+          kubectl config use-context kind-kind
+          kubectl config set-context --current --namespace=default
+          kubectl config view
 
       - name: Helm chart lint
         run: |