fix: Provider produces inconsistent result after importing mongodbatlas_encryption_at_rest

[andreaangiolillo]

Description

Ticket: https://jira.mongodb.org/browse/CLOUDP-220654
Ticket:

This PR fixes a bug in the mongodbatlas_encryption_at_rest resource where the IMPORT and READ logics were different causing tf plan to find differences when the resource was imported.

Link to any related issue(s): #1805

Type of change:

• Bug fix (non-breaking change which fixes an issue). Please, add the "bug" label to the PR.
• New feature (non-breaking change which adds functionality). Please, add the "enhancement" label to the PR.
• Breaking change (fix or feature that would cause existing functionality to not work as expected). Please, add the "breaking change" label to the PR.
• This change requires a documentation update
• Documentation fix/enhancement

Required Checklist:

• I have signed the MongoDB CLA
• I have read the contribution guidelines
• I have checked that this change does not generate any credentials and that they are NOT accidentally logged anywhere.
• I have added tests that prove my fix is effective or that my feature works per HashiCorp requirements
• I have added any necessary documentation (if appropriate)
• I have run make fmt and formatted my code
• If changes include deprecations or removals, I defined an isolated PR with a relevant title as it will be used in the auto-generated changelog.

Testing

Local test

I tested my changes locally by importing the resource and verifying that the plan did not find any changes

terraform import mongodbatlas_encryption_at_rest.kms_encryption 6597de4d840fe16aadbbc713

2024-01-05T11:48:22.089Z [DEBUG] provider: plugin process exited: path=../bin/terraform-provider-mongodbatlas pid=7001
2024-01-05T11:48:22.090Z [DEBUG] provider: plugin exited
2024-01-05T11:48:22.090Z [INFO]  Writing state output to:

Import successful!

The resources that were imported are shown above. These resources are now in
your Terraform state and will henceforth be managed by Terraform.

terraform plan


2024-01-05T11:48:46.390Z [INFO]  backend/local: plan operation completed

No changes. Your infrastructure matches the configuration.

Acceptance tests

• I have updated the acceptance tests to test that the state file does not change on imports.
• I ran the acceptance tests locally and tested that the resource import verify was successful

Running tool: /Users/andrea.angiolillo/.asdf/shims/go test -timeout 300000s -run ^TestAccAdvRSEncryptionAtRest_basicAWS$ github.com/mongodb/terraform-provider-mongodbatlas/internal/service/encryptionatrest

ok  	github.com/mongodb/terraform-provider-mongodbatlas/internal/service/encryptionatrest	13.032s

[maastha]

Suggested change

	func setEmpyArrayForEmptyBlocksReturnedFromImport(newStateFromImport *TfEncryptionAtRestRSModel) {
	func setEmptyArrayForEmptyBlocksReturnedFromImport(newStateFromImport *TfEncryptionAtRestRSModel) {

[maastha]

minor suggestion, LGTM