Update README to explain where to file issues (#4961)

Co-authored-by: Cameron Thornton <[email protected]>

Author: olliefr

README.md

@@ -5,6 +5,7 @@
 - Documentation: https://www.terraform.io/docs/providers/google/index.html
 - [![Gitter chat](https://badges.gitter.im/hashicorp-terraform/Lobby.png)](https://gitter.im/hashicorp-terraform/Lobby)
 - Mailing list: [Google Groups](http://groups.google.com/group/terraform-tool)
+- Issue tracker: [terraform-provider-google](https://github.com/hashicorp/terraform-provider-google/issues/new/choose)
 
 The Terraform Google provider beta is a plugin that allows [Terraform](https://www.terraform.io) to manage resources on Google Cloud Platform. This provider is maintained by the [Terraform team at Google](https://cloudplatform.googleblog.com/2017/03/partnering-on-open-source-Google-and-HashiCorp-engineers-on-managing-GCP-infrastructure.html) and the Terraform team at [HashiCorp](https://www.hashicorp.com/)
 
@@ -37,6 +38,4 @@ This repository is generated by [magic-modules](https://github.com/GoogleCloudPl
 If you wish to work on the provider, you'll need to make changes in [magic-modules](https://github.com/GoogleCloudPlatform/magic-modules). Any changes made directly to this repository will likely be overwritten.
 
 For guidance on how to contribute, see the [contribution guidelines](https://github.com/GoogleCloudPlatform/magic-modules#contributing).
-If you have other development questions we don't cover, please [file an issue](https://github.com/hashicorp/terraform-provider-google/issues/new/choose)!
-
-
+If you have other development questions we don't cover, please [file an issue](https://github.com/hashicorp/terraform-provider-google/issues/new/choose) in the `terraform-provider-google` repository.