New Env Var: `GOOGLEWORKSPACE_OAUTH_SCOPES`

[tgoodsell-tempus]

This PR allows the provider to use a env var GOOGLEWORKSPACE_OAUTH_SCOPES for setting the OAuth Scopes used with the credentials call.

Is necessary when your workspace user is not delegated all scopes/access, but you'd rather not set them in each individual provider block.

[tgoodsell-tempus]

Env Used:

    export GOOGLEWORKSPACE_IMPERSONATED_USER_EMAIL="<redacted>"
    export GOOGLEWORKSPACE_DOMAIN="<redacted>"
    export GOOGLEWORKSPACE_CUSTOMER_ID="<redacted>"
    export GOOGLEWORKSPACE_CREDENTIALS="$HOME/.googleworkspace/<redacted>.json"
    export GOOGLEWORKSPACE_OAUTH_SCOPES="https://www.googleapis.com/auth/admin.directory.group,https://www.googleapis.com/auth/admin.directory.user"

Test Results:

{21-07-08 13:35}tmps-nb-2168:~/Project_WorkDir/terraform-provider-googleworkspace@scope_env_var thomas.goodsell% make testacc TESTARGS="-run=TestAccResourceGroup_basic"   
==> Checking source code against gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test -count=1 $(go list ./...) -v -run=TestAccResourceGroup_basic -timeout 120m
?       github.com/hashicorp/terraform-provider-googleworkspace [no test files]
=== RUN   TestAccResourceGroup_basic
=== PAUSE TestAccResourceGroup_basic
=== CONT  TestAccResourceGroup_basic
--- PASS: TestAccResourceGroup_basic (55.59s)
PASS
ok      github.com/hashicorp/terraform-provider-googleworkspace/internal/provider       55.925s
{21-07-08 13:36}tmps-nb-2168:~/Project_WorkDir/terraform-provider-googleworkspace@scope_env_var thomas.goodsell% make testacc TESTARGS="-run=TestAccResourceUser_basic"    
==> Checking source code against gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test -count=1 $(go list ./...) -v -run=TestAccResourceUser_basic -timeout 120m
?       github.com/hashicorp/terraform-provider-googleworkspace [no test files]
=== RUN   TestAccResourceUser_basic
=== PAUSE TestAccResourceUser_basic
=== CONT  TestAccResourceUser_basic
--- PASS: TestAccResourceUser_basic (86.34s)
PASS
ok      github.com/hashicorp/terraform-provider-googleworkspace/internal/provider       86.640s

[megan07]

I've had a bit more time to play with this. It seems like this is an open issue in the SDK. I'll follow up with them and see if we can figure out a workaround.

[tgoodsell-tempus]

Closing to re-do in the terraform-provider-framework style.