chore: Disables migration test for backup snapshot export until next release version.

[marcosuma]

Description

Follow-up from https://github.com/mongodb/terraform-provider-mongodbatlas/pull/2274 The migration test needs to be disabled since it would actually need us to define the ID properly (and not just any value). I am not sure how I managed to make it successful locally but test was failing since the weekend: https://github.com/mongodb/terraform-provider-mongodbatlas/actions/runs/9151546873/job/25157755777

Link to any related issue(s): CLOUDP-249082

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. A migration guide must be created or updated if the new feature will go in a major version.
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected). Please, add the "breaking change" label to the PR. A migration guide must be created or updated.
• [ ] This change requires a documentation update
• [ ] Documentation fix/enhancement

Required Checklist:

• [x] I have signed the MongoDB CLA
• [x] I have read the contributing guides
• [x] I have checked that this change does not generate any credentials and that they are NOT accidentally logged anywhere.
• [x] I have added tests that prove my fix is effective or that my feature works per HashiCorp requirements
• [x] I have added any necessary documentation (if appropriate)
• [x] I have run make fmt and formatted my code
• [x] 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.
• [x] If changes include removal or addition of 3rd party GitHub actions, I updated our internal document. Reach out to the APIx Integration slack channel to get access to the internal document.

Further comments

[marcosuma]

executed the test for two times: https://github.com/mongodb/terraform-provider-mongodbatlas/actions/runs/9155019403/job/25168593840?pr=2288

but they are failing at the same place of un unrelated test:

Error: -20T09:12:54.517Z [ERROR] sdk.helper_resource: Unexpected error: test_name=TestAccBackupRSOnlineArchiveWithProcessRegion test_terraform_path=/home/runner/work/_temp/a821a4f9-3c22-4498-aee5-2e31235767db/terraform test_working_directory=/tmp/plugintest1718490434 test_step_number=1 error="Check failed: Check 1/1 error: cluster(664b0a7afe5fdc7345c62f0d:664b0f48227f1c4b6f076b44) working sample data set error FAILED"
=== NAME  TestAccBackupRSOnlineArchiveWithProcessRegion
    resource_online_archive_test.go:183: Step 1/4 error: Check failed: Check 1/1 error: cluster(664b0a7afe5fdc7345c62f0d:664b0f48227f1c4b6f076b44) working sample data set error FAILED
querying for job 
Error: -20T09:12:54.617Z [ERROR] sdk.helper_resource: Unexpected error: test_name=TestAccBackupRSOnlineArchive test_terraform_path=/home/runner/work/_temp/a821a4f9-3c22-4498-aee5-2e31235767db/terraform test_working_directory=/tmp/plugintest3344522499 test_step_number=1 error="Check failed: Check 1/1 error: cluster(664b0a7a227f1c4b6f0761b9:664b0f48fe5fdc7345c63a4c) working sample data set error FAILED"
=== NAME  TestAccBackupRSOnlineArchive
    resource_online_archive_test.go:32: Step 1/7 error: Check failed: Check 1/1 error: cluster(664b0a7a227f1c4b6f0761b9:664b0f48fe5fdc7345c63a4c) working sample data set error FAILED
--- FAIL: TestAccBackupRSOnlineArchive (2632.70s)
--- FAIL: TestAccBackupRSOnlineArchiveWithProcessRegion (2672.84s)

The test I've changed to be skipped is instead working correctly:

=== RUN   TestMigBackupSnapshotExportJob_basic
    resource_cloud_backup_snapshot_export_job_migration_test.go:10: Skipping because version 1.16.0 below 1.16.1
--- SKIP: TestMigBackupSnapshotExportJob_basic (0.00s)