Merge pull request #3668 from mermaid-js/3659_height_handling

#3659 Adding height when not using maxWidth

packages/mermaid/src/setupGraphViewbox.js

@@ -26,6 +26,7 @@ export const calculateSvgSizeAttrs = function (height, width, useMaxWidth) {
     attrs.set('width', '100%');
     attrs.set('style', `max-width: ${width}px;`);
   } else {
+    attrs.set('height', height);
     attrs.set('width', width);
   }
   return attrs;