chore: update README and use sensible workflow names

.github/workflows/cr-master.yaml → .github/workflows/helm-charts-release.yaml

-name: Release Helm Charts
+name: "helm-charts/release"
 
 on:
   push:

.github/workflows/cr-pull-request.yaml → .github/workflows/helm-charts-test.yaml

-name: Test Helm Charts
+name: "helm-charts/test"
 
 on: pull_request
 

.github/workflows/terraform-master.yaml → .github/workflows/terraform-apply.yaml

-name: Terraform Apply
+name: "terraform/apply"
 
 on:
   push:

.github/workflows/terraform-pull-request.yaml → .github/workflows/terraform-plan.yaml

-name: Terraform Plan
+name: "terraform/plan"
 
 on:
   pull_request:

README.md

 # InfluxData Helm Charts
 
 [![License](https://img.shields.io/badge/license-MIT-green.svg)](./LICENSE)
-[![](https://github.com/influxdata/helm-charts/workflows/Release%20Master/badge.svg?branch=master)](https://github.com/influxdata/helm-charts/actions)
+[![](https://github.com/influxdata/helm-charts/workflows/helm-charts%2Frelease/badge.svg?branch=master)](https://github.com/influxdata/helm-charts/actions)
 
 This functionality is in beta and is subject to change. The code is provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features.