Removes the force option for helm

We are seeing the same issue we saw for the gitlab release when upgrading to helm3

Error: UPGRADE FAILED: an error occurred while rolling back the release. original upgrade error: failed to replace object: Service "thanos-bucket-cache-memcached-metrics" is invalid: spec.clusterIP: Invalid value: "": field is immutable: failed to replace object: Service "thanos-bucket-cache-memcached-metrics" is invalid: spec.clusterIP: Invalid value: "": field is immutable

https://ops.gitlab.net/gitlab-com/gl-infra/k8s-workloads/gitlab-helmfiles/-/jobs/2661679

This removes the force flag for helmfiles, similar to gitlab-com/gl-infra/delivery#1399 (comment 468380625)