[issue-2401] Added pod security context for Fission Components (#2449)

Following component has been updated with securityContext -
1. buildermgr
2. controller
3. executor
4. kubewatcher
5. router
6. timer
7. storagesvc

* Removed the security context from fetcher as per the offline discussion

skaffold.yaml

@@ -56,6 +56,12 @@ deploy:
         # Use /var/log directory for kind logs export
         terminationMessagePath: /var/log/termination-log
         terminationMessagePolicy: FallbackToLogsOnError
+        executor.securityContext.enabled: true
+        router.securityContext.enabled: true
+        buildermgr.securityContext.enabled: true
+        controller.securityContext.enabled: true
+        kubewatcher.securityContext.enabled: true
+        storagesvc.securityContext.enabled: true
       wait: true
     flags:
       install: