also shrink the composer bar when you don't have permissions

src/skins/vector/css/matrix-react-sdk/views/rooms/_MessageComposer.scss

@@ -205,4 +205,8 @@ limitations under the License.
     .mx_MessageComposer_input {
         min-height: 50px;
     }
+
+    .mx_MessageComposer_noperm_error {
+        height: 50px;
+    }
 }