fix(grpc): remove the dead Refresh item from the method picker

It has never had an onSelect. Introduced inert in #193 and carried
through the codebase split, so clicking it only ever closed the dropdown.
Reload Schema in the message editor's schema dropdown does the job it
looked like it was for.

apps/yaak-client/components/GrpcRequestPane.tsx

@@ -194,13 +194,6 @@ export function GrpcRequestPane({
               type: "default",
               shortLabel: o.label,
             }))}
-            itemsAfter={[
-              {
-                label: "Refresh",
-                type: "default",
-                leftSlot: <Icon size="sm" icon="refresh" />,
-              },
-            ]}
           >
             <Button
               size="sm"