[simple-chart] Remove leading quotes from comment strings when excel …

…sneaks them in (#6780)

* remove leading quotes from comment strings when excel sneaks them in

* More accurate regex replacement

* match first line quote

* handle first char and linebreak cases, with \n replacement as necessary

cfgov/unprocessed/js/routes/on-demand/simple-chart/simple-chart.js

@@ -61,6 +61,9 @@ function fetchData( url, isCSV ) {
 
     return prom.then( d => {
       if ( isCSV ) {
+        /* Excel can put quotes at the start of our # or // comments
+           This strips those quotes */
+        d = d.replace( /^"(#|\/\/)|(\n)"(#|\/\/)/g, '$1$2$3' );
         d = Papa.parse( d, {
           header: true, comments: true, skipEmptyLines: true
         } ).data;