docs: fix the CI pipeline badge url (#4)

Author: ocofaigh

README.md

@@ -1,6 +1,6 @@
 # IBM Secure Landing Zone VPC Module
 
-[![Build Status](https://github.com/terraform-ibm-modules/terraform-ibm-landing-zone-vpc/actions/workflows/main.yml/badge.svg)](https://github.com/terraform-ibm-modules/terraform-ibm-landing-zone-vpc/actions/workflows/main.yml)
+[![Build Status](https://github.com/terraform-ibm-modules/terraform-ibm-landing-zone-vpc/actions/workflows/ci.yml/badge.svg)](https://github.com/terraform-ibm-modules/terraform-ibm-landing-zone-vpc/actions/workflows/ci.yml)
 [![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release)
 [![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white)](https://github.com/pre-commit/pre-commit)