check kubernetes version only when the version changed (#54090)

* check kubernetes version only when the version changed

* fix typo

lib/ansible/modules/cloud/azure/azure_rm_aks.py

@@ -539,11 +539,11 @@ class AzureRMManagedCluster(AzureRMModuleBase):
             if agentpoolcount > 1:
                 self.fail('You cannot specify more than one agent_pool_profiles currently')
 
-            available_versions = self.get_all_versions()
-            if self.kubernetes_version not in available_versions.keys():
-                self.fail("Unsupported kubernetes version. Excepted one of {0} but get {1}".format(available_versions.keys(), self.kubernetes_version))
             if not response:
                 to_be_updated = True
+                available_versions = self.get_all_versions()
+                if self.kubernetes_version not in available_versions.keys():
+                    self.fail("Unsupported kubernetes version. Expected one of {0} but got {1}".format(available_versions.keys(), self.kubernetes_version))
             else:
                 self.results = response
                 self.results['changed'] = False
@@ -582,7 +582,7 @@ class AzureRMManagedCluster(AzureRMModuleBase):
                         to_be_updated = True
 
                     if response['kubernetes_version'] != self.kubernetes_version:
-                        upgrade_versions = available_versions.get(response['kubernetes_version'])
+                        upgrade_versions = available_versions.get(response['kubernetes_version']) or available_versions.keys()
                         if upgrade_versions and self.kubernetes_version not in upgrade_versions:
                             self.fail('Cannot upgrade kubernetes version to {0}, supported value are {1}'.format(self.kubernetes_version, upgrade_versions))
                         to_be_updated = True