add compute_instance_helpers.go.erb to the list of compiled files

[daniel-cit]

Add the file compute_instance_helpers.go.erb to the list of files that need to be compiled before been copied to downstream terraform-google-conversion repo.

Related to GoogleCloudPlatform/terraform-google-conversion#572

Release Note Template for Downstream PRs (will be copied)

Compile erb template before copy of compute_instance_helpers.go file

[modular-magician]

Hello! I am a robot who works on Magic Modules PRs.

I have detected that you are a community contributor, so your PR will be assigned to someone with a commit-bit on this repo for initial review.

Thanks for your contribution! A human will be with you soon.

@ndmckinley, please review this PR or find an appropriate assignee.

[nat-henderson]

I'll wait for the generator to finish then merge. :)

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

TF Conversion: Diff ( 1 file changed, 1 insertion(+), 41 deletions(-))

[modular-magician]

Oops! It looks like no changelog entry is attached to this PR. Please include a release note block in the PR body, as described in https://github.com/GoogleCloudPlatform/magic-modules/blob/master/.ci/RELEASE_NOTES_GUIDE.md:

```release-note:TYPE
Release note
```

[nat-henderson]

Cool, I see you edited it, I'll rerun. /gcbrun

[modular-magician]

I have triggered VCR tests based on this PR's diffs. See the results here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=156435"

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

TF Conversion: Diff ( 1 file changed, 1 insertion(+), 41 deletions(-))

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccDataSourceSpannerInstance_basic|TestAccActiveDirectoryDomainTrust_activeDirectoryDomainTrustBasicExample|TestAccBigqueryDataTransferConfig|TestAccComposerEnvironment_withUpdateOnCreate|TestAccFilestoreInstance_filestoreInstanceBasicExample|TestAccFilestoreInstance_update|TestAccOSLoginSSHPublicKey_osLoginSshKeyExpiry You can view the result here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=156451"