fix doc links and validation error message

Author: cadenmarchese

python/az/aro/azext_aro/_validators.py

@@ -128,8 +128,8 @@ def validate_pull_secret(namespace):
                 namespace.pull_secret = file.read().rstrip('\n')
 
         if not isinstance(json.loads(namespace.pull_secret), dict):
-            raise Exception()
-    except Exception as e:
+            raise ValueError("Pull secret must be a valid JSON object")
+    except (ValueError, json.JSONDecodeError) as e:
         raise InvalidArgumentValueError("Invalid --pull-secret.") from e
 
 

python/az/aro/azext_aro/aaz/latest/network/vnet/__cmd_group.py

@@ -14,7 +14,7 @@
 class __CMDGroup(AAZCommandGroup):
     """Check if a private IP address is available for use within a virtual network.
 
-    To learn more about Virtual Networks visit https://docs.microsoft.com/azure/virtual-network/virtual-network-manage-network.
+    To learn more about Virtual Networks visit https://learn.microsoft.com/azure/virtual-network/virtual-network-manage-network.
     """
     pass
 

python/az/aro/azext_aro/aaz/latest/network/vnet/subnet/__cmd_group.py

@@ -14,7 +14,7 @@
 class __CMDGroup(AAZCommandGroup):
     """Manage subnets in an Azure Virtual Network.
 
-    To learn more about subnets visit https://docs.microsoft.com/azure/virtual-network/virtual-network-manage-subnet.
+    To learn more about subnets visit https://learn.microsoft.com/azure/virtual-network/virtual-network-manage-subnet.
     """
     pass