Added missing update_mask parameter to update operation

[xpr0ger]

Added update_mask parameter for update private cloud request b/529713679

Release Note Template for Downstream PRs (will be copied)

See Write release notes for guidance.

vmwareengine: added correct `update_mask` value to private cloud update request 

[github-actions]

Googlers: For automatic test runs see go/terraform-auto-test-runs.

@slevenick, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes for commit 943a1b8:

Diff report

Your PR generated the following diffs in downstream repositories:

Repository	Diff Link	Changes
google provider	View Diff	1 file changed, 53 insertions(+), 21 deletions(-)
google-beta provider	View Diff	1 file changed, 53 insertions(+), 21 deletions(-)

Test report

Analytics

Total Tests	Passed	Skipped	Affected
15	9	6	0

Affected Service Packages

• vmwareengine

Learn how VCR tests work

---

Step 1: Replaying Mode

🟢 All tests passed in Replaying mode! No Recording was needed.

View the replaying VCR build log

@xpr0ger, @slevenick VCR tests complete for 943a1b8!

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes for commit b89db4b:

Diff report

Your PR generated the following diffs in downstream repositories:

Repository	Diff Link	Changes
google provider	View Diff	1 file changed, 53 insertions(+), 21 deletions(-)
google-beta provider	View Diff	1 file changed, 53 insertions(+), 21 deletions(-)

Test report

Analytics

Total Tests	Passed	Skipped	Affected
15	9	6	0

Affected Service Packages

• vmwareengine

Learn how VCR tests work

---

Step 1: Replaying Mode

🟢 All tests passed in Replaying mode! No Recording was needed.

View the replaying VCR build log

@xpr0ger, @slevenick VCR tests complete for b89db4b!

[slevenick]

Please do a local review with a Google engineer from the service team as described at go/terraform-service-review. Let me know when that's finished and I'll follow up with final review & merge.

[slevenick]

Please add an update test for this resource and this field. I'd like to make sure this keeps working