add vpc_connector to update

[megan07]

Added vpc_connector to update function.

Fixes hashicorp/terraform-provider-google#5811

Release Note Template for Downstream PRs (will be copied)

cloudfunctions: fixed `vpc_connector` to be updated properly in `google_cloudfunctions_function`

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 2 files changed, 26 insertions(+), 7 deletions(-))
Terraform Beta: Diff ( 2 files changed, 26 insertions(+), 7 deletions(-))

[modular-magician]

Oops! It looks like you're using an unknown release-note type in your changelog entries:

• REPLACEME

Please only use the types listed in https://github.com/GoogleCloudPlatform/magic-modules/blob/master/.ci/RELEASE_NOTES_GUIDE.md.

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 2 files changed, 26 insertions(+), 7 deletions(-))
Terraform Beta: Diff ( 2 files changed, 26 insertions(+), 7 deletions(-))