fixing invalid subnet validation in compute instance (#36711)

* fixing sweep job service response parsing issue

* fixing sweep job service response parsing issue

* raising a work around for cmd job and spark job name lowering case

* fixing black issue

* fixing serialization issue in sweep job

* include black fix

* found and fix the issue in compute validation

* fixing a corrupt wokspace arm template

* fixing the failed test case

* updating the date for 1.18.0 release

* removing empty section

* adding in progress version details

* adding IDC code reviewers

* correcting the directory path

* lint fix

* adding change log entry

* addressing review comment

* fixing ut

* addressing api review comment

* adding a fix for subnet validation in compute instance

* my py fix

Author: achauhan-scc

sdk/ml/azure-ai-ml/azure/ai/ml/entities/_compute/compute_instance.py

@@ -344,7 +344,7 @@ def _to_dict(self) -> Dict:
         return res
 
     def _set_full_subnet_name(self, subscription_id: str, rg: str) -> None:
-        if self.network_settings:
+        if self.network_settings and (self.network_settings.vnet_name or self.network_settings.subnet):
             self.subnet = get_subnet_str(
                 self.network_settings.vnet_name,
                 self.network_settings.subnet,