feat: ClientRpc no longer need Rpc prefix (#2086)

Instead of doing
```cs
[ClientRpc]
public void RpcPepe() {}
```

You can now do
```cs
[ClientRpc]
public void Pepe() {}
```

We actually tried to remove them a while ago. The way the weaver worked
back then caused an infinite recursion.

Since the Command rewrite that allows virtuals, this is no longer
a problem.  So we can drop this requirement.

Co-authored-by: Paul Pacheco <paul.pacheco@aa.com>

Assets/Mirror/Editor/Weaver/Processors/RpcProcessor.cs

@@ -112,12 +112,6 @@ public static MethodDefinition ProcessRpcCall(TypeDefinition td, MethodDefinitio
 
         public static bool ProcessMethodsValidateRpc(MethodDefinition md)
         {
-            if (!md.Name.StartsWith("Rpc"))
-            {
-                Weaver.Error($"{md.Name} must start with Rpc.  Consider renaming it to Rpc{md.Name}", md);
-                return false;
-            }
-
             if (md.IsStatic)
             {
                 Weaver.Error($"{md.Name} must not be static", md);

Assets/Mirror/Tests/Editor/ClientRpcTest.cs

@@ -8,7 +8,7 @@ class ClientRpcBehaviour : NetworkBehaviour
         public event Action<int> onSendInt;
 
         [ClientRpc]
-        public void RpcSendInt(int someInt)
+        public void SendInt(int someInt)
         {
             onSendInt?.Invoke(someInt);
         }
@@ -40,7 +40,7 @@ public void RpcIsCalled()
                 callCount++;
                 Assert.That(incomingInt, Is.EqualTo(someInt));
             };
-            hostBehaviour.RpcSendInt(someInt);
+            hostBehaviour.SendInt(someInt);
             ProcessMessages();
             Assert.That(callCount, Is.EqualTo(1));
         }

Assets/Mirror/Tests/Editor/Weaver/WeaverClientRpcTests.cs

@@ -10,12 +10,6 @@ public void ClientRpcValid()
             Assert.That(weaverErrors, Is.Empty);
         }
 
-        [Test]
-        public void ClientRpcStartsWithRpc()
-        {
-            Assert.That(weaverErrors, Contains.Item("DoesntStartWithRpc must start with Rpc.  Consider renaming it to RpcDoesntStartWithRpc (at System.Void WeaverClientRpcTests.ClientRpcStartsWithRpc.ClientRpcStartsWithRpc::DoesntStartWithRpc())"));
-        }
-
         [Test]
         public void ClientRpcCantBeStatic()
         {