AWS For Fluent Bit chart fails on K8S 1.20 due to deprecated apiVersion in templates

**Describe the bug**
A concise description of what the bug is.

The `clusterrole.yaml` and `clusterrolebinding.yaml` templates have a deprecated apiVersion in Kubernetes 1.20. Trying to deploy the chart results in the following errors:

````
Error: malformed chart or values:
templates/clusterrole.yaml: the kind "rbac.authorization.k8s.io/v1beta1 ClusterRole" is deprecated in favor of "rbac.authorization.k8s.io/v1 ClusterRole"
templates/clusterrolebinding.yaml: the kind "rbac.authorization.k8s.io/v1beta1 ClusterRoleBinding" is deprecated in favor of "rbac.authorization.k8s.io/v1 ClusterRoleBinding"
````

**Steps to reproduce**

- Provision an EKS Cluster with Kubernetes 1.20.
- Attempt to deploy the helm chart

**Expected outcome**

The chart deploys successfully.

**Environment**
Terraform 0.14.5
AWS EKS
Kubernetes 1.20

* Chart name: aws-for-fluent-bit
* Chart version: 0.1.12
* Kubernetes version: 1.20
* Using EKS (yes/no), if so version?
Yes, eks.3

**Additional Context**:

Start with templates/clusterrole.yaml and templates/clusterrolebinding.yaml, then render the aws-for-fluent-bit chart with Helm for Kubernetes 1.20. Update the deprecated RBAC API versions and verify the rendered chart deploys successfully to an EKS 1.20 cluster.

Written by the indexing model from the issue text.