Added send_empty_value to is_ca field to force sending false

[melinath]

Resolved hashicorp/terraform-provider-google#10239 by ensuring that the Terraform value will be used as expected.

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• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
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Release Note Template for Downstream PRs (will be copied)

privateca: Fixed bug where `is_ca` could not be set to false for google_privateca_ca_pool

[slevenick]

We may need this on other boolean fields in these resources if the API treats them all in the same way?

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 5 files changed, 5 insertions(+), 5 deletions(-))
Terraform Beta: Diff ( 6 files changed, 6 insertions(+), 6 deletions(-))
TF Conversion: Diff ( 3 files changed, 3 insertions(+), 3 deletions(-))
TF OiCS: Diff ( 1 file changed, 1 insertion(+), 1 deletion(-))

[melinath]

@slevenick The other impacted bool fields (allow_subject_passthrough & allow_subject_alt_names_passthrough) are already send_empty_value: true

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccServiceNetworkingPeeredDNSDomain_basic|TestAccPrivatecaCaPool_privatecaCapoolAllFieldsExample|TestAccPrivatecaCaPool_privatecaCapoolEmptyBaseline|TestAccPrivatecaCertificate_privatecaCertificateConfigExample|TestAccPrivatecaCertificate_privatecaCertificateNoAuthorityExample You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=208993

[melinath]

Leaving this to be fixed in a different way.