Expand documentation on contributing new resources (#514)
Expand documentation on contributing new resources (#514)

* Expand documentation on contributing new resources

* Remove description about making changes in terraform-validator repo

* Update docs/contributing/add_new_resource.md

Co-authored-by: Stephen Lewis (Burrows) <b5b0f42cbd0e70186a1daa88977913a3dfed264b@gmail.com>

Co-authored-by: Stephen Lewis (Burrows) <b5b0f42cbd0e70186a1daa88977913a3dfed264b@gmail.com>
GoogleCloudPlatform/terraform-validator,GoogleCloudPlatform/terraform-validator