fix: remove action feature flag and include execution (#9727)

# Which Problems Are Solved

Actions v2 is not a feature flag anymore, include functionality on
executions is not used and json tags of proto messages are handled
incorrectly.

# How the Problems Are Solved

- Remove actions from the feature flags on system and instance level
- Remove include type on executions, only in the API, later maybe in the
handling logic as well
- Use protojson in request and response handling of actions v2

# Additional Changes

- Correct integration tests for request and response handling
- Use json.RawMessage for events, so that the event payload is not
base64 encoded
- Added separate context for async webhook calls, that executions are
not cancelled when called async

# Additional Context

Related to #9759 
Closes #9710

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/api/grpc/action/v2beta/target.go

@@ -14,9 +14,6 @@ import (
 )
 
 func (s *Server) CreateTarget(ctx context.Context, req *action.CreateTargetRequest) (*action.CreateTargetResponse, error) {
-	if err := checkActionsEnabled(ctx); err != nil {
-		return nil, err
-	}
 	add := createTargetToCommand(req)
 	instanceID := authz.GetInstance(ctx).InstanceID()
 	createdAt, err := s.command.AddTarget(ctx, add, instanceID)
@@ -35,9 +32,6 @@ func (s *Server) CreateTarget(ctx context.Context, req *action.CreateTargetReque
 }
 
 func (s *Server) UpdateTarget(ctx context.Context, req *action.UpdateTargetRequest) (*action.UpdateTargetResponse, error) {
-	if err := checkActionsEnabled(ctx); err != nil {
-		return nil, err
-	}
 	instanceID := authz.GetInstance(ctx).InstanceID()
 	update := updateTargetToCommand(req)
 	changedAt, err := s.command.ChangeTarget(ctx, update, instanceID)
@@ -55,9 +49,6 @@ func (s *Server) UpdateTarget(ctx context.Context, req *action.UpdateTargetReque
 }
 
 func (s *Server) DeleteTarget(ctx context.Context, req *action.DeleteTargetRequest) (*action.DeleteTargetResponse, error) {
-	if err := checkActionsEnabled(ctx); err != nil {
-		return nil, err
-	}
 	instanceID := authz.GetInstance(ctx).InstanceID()
 	deletedAt, err := s.command.DeleteTarget(ctx, req.GetId(), instanceID)
 	if err != nil {