GCP Label Selector Experiment Charts and GCP Experiments Refactor (#532)

* added gcp-vm-instance-stop-by-label charts

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* updated experiment charts

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* added gcp-vm-disk-loss-by-label-charts; updated gcp-vm-disk-loss and gcp-vm-instance-stop charts to add sequence to engine manifest and removed device name from gcp-vm-disk-loss manifests

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* finalised charts

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* updated chart comments

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* updated AUTO_SCALING_GROUP env to MANAGED_INSTANCE_GROUP env

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* finalised charts for all GCP experiments

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* updated provider and author details in gcp-vm-instance-stop-by-label experiment

Signed-off-by: neelanjan00 <neelanjan@chaosnative.com>

* updated docs links

Signed-off-by: Neelanjan Manna <neelanjan.manna@harness.io>

* removed pods/exec rbac, updated keywords

Signed-off-by: Neelanjan Manna <neelanjan.manna@harness.io>

* updated chartserviceversion, package

Signed-off-by: Neelanjan Manna <neelanjan.manna@harness.io>

Co-authored-by: Udit Gaurav <35391335+uditgaurav@users.noreply.github.com>

charts/gcp/gcp-vm-instance-stop/experiment.yaml

@@ -29,11 +29,7 @@ spec:
       # Track and get the runner, experiment, and helper pods log 
       - apiGroups: [""]
         resources: ["pods/log"]
-        verbs: ["get","list","watch"]  
-      # for creating and managing to execute comands inside target container
-      - apiGroups: [""]
-        resources: ["pods/exec"]
-        verbs: ["get","list","create"]
+        verbs: ["get","list","watch"]
       # for configuring and monitor the experiment job by the chaos-runner pod
       - apiGroups: ["batch"]
         resources: ["jobs"]
@@ -74,8 +70,8 @@ spec:
     - name: RAMP_TIME
       value: ''
 
-    # enable or disable; shall be enabled if the target instance is a part of an auto scaling group.
-    - name: AUTO_SCALING_GROUP
+    # enable or disable; shall be set to enable if the target instances are a part of a managed instance group
+    - name: MANAGED_INSTANCE_GROUP
       value: 'disable'
     
     # Instance name of the target vm instance(s)