Fix NOT_AUTHENTICATED errors in Content Library tests

[adambarreiro]

This PR fixes the test failure:

=== RUN   TestAccVcfaContentLibraryTenant
    resource_vcfa_content_library_test.go:285: Step 4/6 error: Error running pre-apply refresh: exit status 1
        
        Error: error getting Storage Class by Name 'vSAN Default Storage Policy': error retrieving all entities of type 'Storage Class': error getting all pages for endpoint https://my-vcfa.com/cloudapi/vcf/storageClasses/: error in HTTP GET request: NOT_AUTHENTICATED - [ 3258-2025-03-07-00-07-32-260--218b64dc-ad8d-43c6-9f9f-4c6eff270d9e ] This operation is denied.
        
          with data.vcfa_storage_class.sc-tenant,
          on terraform_plugin_test.tf line 167, in data "vcfa_storage_class" "sc-tenant":
         167: data "vcfa_storage_class" "sc-tenant" {
        
--- FAIL: TestAccVcfaContentLibraryTenant (220.57s)

The issue happens because there is one test, TestAccVcfaContentLibraryItemTenant, which is run before TestAccVcfaContentLibraryTenant, that creates an Organization user and performs a login with it, caching its data in the client cache. When the test finishes, the user is destroyed, but it remains in the client cache.

When TestAccVcfaContentLibraryTenant kicks in afterwards, it creates again the same user (it re-uses same HCL), so when the login comes, it reuses wrong cached info, therefore all subsequent queries will end up with NOT_AUTHENTICATED errors.

The fix consists of resetting the cached clients when these kind of tests complete.

Extra fix: Disable anti-virus scanning in created Org in these tests, to avoid blocking tasks.

To reproduce:

go test -tags functional -vcfa-add-provider -run 'TestAccVcfaContentLibraryTenant|TestAccVcfaContentLibraryItemTenant' -v -timeout 0

This will fail without this fix with the error above. With the fix, both should pass

[lvirbalas]

Beautiful find!