move scroll of code editor inside editor

Signed-off-by: Maxim Sukharev <[email protected]>

Author: smacker

frontend/src/App.less

@@ -69,7 +69,7 @@ body {
 // make modal window "fullscreen"
 // margins are hard-coded in bootstrap, so it's hard-coded here too
 .modal-body {
-    max-height: ~'calc(100vh - 80px)';
+    height: ~'calc(100vh - 80px)';
     overflow-y: auto;
 }
 
@@ -78,3 +78,8 @@ body {
         max-height: ~'calc(100vh - 120px)';
     }
 }
+
+.uast-editor,
+.react-codemirror2 {
+    height: 100%;
+}