refactor(fgs/async): using auto-gen style to replace old coding

[Lance52259]

What this PR does / why we need it:
New acceptance to coverage the destination configuration structure when it is empty.
Refactor the async configuration resource and using auto-generate style to replace the old coding.

Which issue this PR fixes:
(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)
fixes #xxx

Special notes for your reviewer:

Release note:

1. new acceptance to coverage the destination configuration structure when it is empty.
2. using auto-gen style to replace old coding.

PR Checklist

• [x Tests added/passed.

./scripts/coverage.sh -o fgs -f TestAccAsyncInvokeConfig
Prepare to calculate the coverage the following command:
TF_ACC=1 go test "./huaweicloud/services/acceptance/fgs" -v -coverprofile="./huaweicloud/services/acceptance/fgs/fgs_coverage.cov" -coverpkg="./huaweicloud/services/fgs" -run TestAccAsyncInvokeConfig -timeout 360m -parallel 10
=== RUN   TestAccAsyncInvokeConfig_basic
=== PAUSE TestAccAsyncInvokeConfig_basic
=== RUN   TestAccAsyncInvokeConfig_withoutDestConfigs
=== PAUSE TestAccAsyncInvokeConfig_withoutDestConfigs
=== CONT  TestAccAsyncInvokeConfig_basic
=== CONT  TestAccAsyncInvokeConfig_withoutDestConfigs
--- PASS: TestAccAsyncInvokeConfig_withoutDestConfigs (21.66s)
--- PASS: TestAccAsyncInvokeConfig_basic (28.94s)
PASS
coverage: 14.6% of statements in ./huaweicloud/services/fgs
ok      github.com/huaweicloud/terraform-provider-huaweicloud/huaweicloud/services/acceptance/fgs       29.003s coverage: 14.6% of statements in ./huaweicloud/services/fgs

• Documentation updated.

• Schema updated.

• CheckDeleted.

  • a. During query operation (Read Context)
    aa. Resource not found
    >>>>>> Paste the screenshot here <<<<<<

  • b. During delete/disassociate/unbind operation (Delete Context)
    ba. Resource not found
    >>>>>> Paste the screenshot here <<<<<<

[deer-hang]

/approve
/lgtm

[github-ci-robot]

This PR has been approved by: @deer-hang

/approve
/lgtm