tgc-revival: set missing required field in flatten object with unknown

[zli82016]

If the flatten object is nil in cai asset data, don't return nil. Instead, create an empty object. If any required field is "unknown", then the object will have this field.

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[modular-magician]

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

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Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 55 files changed, 766 deletions(-))

[modular-magician]

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

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 55 files changed, 248 insertions(+), 1014 deletions(-))

[modular-magician]

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

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 55 files changed, 248 insertions(+), 1014 deletions(-))

[modular-magician]

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

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 55 files changed, 744 insertions(+), 766 deletions(-))

[modular-magician]

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

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 3 files changed, 6 insertions(+), 28 deletions(-))

[modular-magician]

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

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 3 files changed, 6 insertions(+), 28 deletions(-))

[zli82016]

These are the main change.

Other changes are refactoring.

[github-actions]

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