fix: Update bootstrap README.md steps & terraform.example.tfvars (#470)

* Update README.md re: terraform.example.tfvars

Update README.md to match Jenkins. Change from copy `terraform.example.tfvars` to rename to avoid creating multiple input variable definition files.

* 0-bootstrap Update README.md sequence

Change sequence to run `terraform init` immediately after  `cp backend.tf.example backend.tf`.

Current sequence has `terraform output terraform_service_account` immediately after `cp backend.tf.example backend.tf` which generates  `Backend reinitialization required. Please run "terraform init".`

* 0-bootstrap -  Update README.md 

Change 'from previous step' to 'from Terraform's state' to make wording less dependent on precise order of steps

* Add mv command for copy/paste

Add mv terraform.example.tfvars terraform.tfvars for easy copy/paste

* Update README.md formatting error

Correct spacing formatting error in my last commit

0-bootstrap/README.md

@@ -108,27 +108,24 @@ your current Jenkins manager (master) environment.
 ## Deploying with Cloud Build
 
 1. Go to the `0-bootstrap` folder.
-1. Copy the `tfvars` file:
-   ```
-   cp terraform.example.tfvars terraform.tfvars
-   ```
-1. Update the `terraform.tfvars` file with values from your environment.
+1. Rename `terraform.example.tfvars` to `terraform.tfvars` and update the file with values from your environment:
+    ```
+    mv terraform.example.tfvars terraform.tfvars
+    ```
 1. Run `terraform init`.
 1. Run `terraform plan` and review the output.
 1. To run terraform-validator steps please follow the [instructions](https://github.com/forseti-security/policy-library/blob/master/docs/user_guide.md#install-terraform-validator) in the **Install Terraform Validator** section and install version `2021-03-22`. You will also need to rename the binary from `terraform-validator-<your-platform>` to `terraform-validator`.
     1. Run `terraform plan -input=false -out bootstrap.tfplan`
     1. Run `terraform show -json bootstrap.tfplan > bootstrap.json`
     1. Run `terraform-validator validate bootstrap.json --policy-path="../policy-library" --project <A-VALID-PROJECT-ID>` and check for violations (`<A-VALID-PROJECT-ID>` must be an existing project you have access to, this is necessary because Terraform-validator needs to link resources to a valid Google Cloud Platform project).
 1. Run `terraform apply`.
-1. Run `terraform output gcs_bucket_tfstate` to get your Google Cloud bucket
-   from the previous step.
+1. Run `terraform output terraform_service_account` to get the email address of the admin. You need this address in a later procedure.
+1. Run `terraform output gcs_bucket_tfstate` to get your Google Cloud bucket name from Terraform's state.
 1. Copy the backend:
    ```
    cp backend.tf.example backend.tf
    ```
 1. Update `backend.tf` with the name of your Cloud Storage bucket.
-1. Run `terraform output terraform_service_account` to get the email address of the
-   admin. You need this address in a later procedure.
 1. Re-run `terraform init`. When you're prompted, agree to copy state to
    Cloud Storage.
 1. (Optional) Run `terraform apply` to verify that state is configured