DHFPROD-1526 - Beautify trace errors on QuickStart UI (#1718)

* beautified trace error

* updated css for error message

Author: brucean52

quick-start/src/main/ui/app/shared/components/ml-error/ml-error.component.scss

@@ -7,6 +7,8 @@
 .format-string {
   border: 1px solid rgba(0,0,0,0.10);
   padding: 10px;
+  max-height: 300px;
+  overflow: scroll;
 }
 
 .header {

quick-start/src/main/ui/app/shared/components/trace-viewer/trace-viewer-ui.component.scss

@@ -25,6 +25,7 @@ app-trace-viewer {
 .layout-body {
   position: relative;
   flex: 1;
+  background-color: white;
 }
 
 .gray {