Change arial to verdana and always use sans serif verdana

Author: marthacryan

dash/dash-renderer/src/components/error/CallbackGraph/CallbackGraphContainer.css

@@ -26,7 +26,7 @@
     box-sizing: border-box;
     background: rgba(255, 255, 255, 0.9);
     border: 2px solid #ccc;
-    font-family: 'Arial', sans-serif;
+    font-family: Verdana, sans-serif;
 }
 
 .dash-callback-dag--message {
@@ -36,7 +36,7 @@
     align-items: center;
     height: 100%;
     line-height: 2em;
-    font-family: 'Arial', sans-serif;
+    font-family: Verdana, sans-serif;
 }
 
 .dash-callback-dag--layoutSelector {

dash/dash-renderer/src/components/error/CallbackGraph/CallbackGraphContainerStylesheet.js

@@ -3,7 +3,7 @@ const stylesheet = [
         selector: '*',
         style: {
             'font-size': 12,
-            'font-family': '"Arial", sans-serif'
+            'font-family': 'Verdana, sans-serif'
         }
     },
 

dash/dash-renderer/src/components/error/menu/DebugMenu.css

@@ -106,7 +106,7 @@
     right: 8px;
     display: flex;
     flex-direction: column;
-    font-family: Verdana;
+    font-family: Verdana, sans-serif;
     font-size: 14px;
     justify-content: center;
     align-items: center;