Fix error thrown when successfully submitting workout due to json->JSON and improve look of graphs

templates/attemptv2.html

@@ -48,6 +48,7 @@
                     <svg id="graph" class="bg-white shadow-md"></svg>
                 </div>
             </div>
+            <img src="http://127.0.0.1:5000/user/1/workout/2" alt="No image">
         </div>
     </div>
     <script>
@@ -115,7 +116,7 @@
                 },
                 body: JSON.stringify({ workout: workout }),
             }).then(res => res.json())
-                .then(res => swal("Submitted", json.stringify(res), "success"))
+                .then(res => swal("Submitted", JSON.stringify(res), "success"))
                 .catch(err => swal("Failed to submit workout", err.message, "error"));
 
             workout = [];
@@ -163,7 +164,7 @@
         const line = d3.line()
             .x((d) => xScale(d.x))
             .y((d) => yScale(d.y))
-            .curve(d3.curveCardinal);
+            .curve(d3.curveCardinal.tension(0.25));
 
         // Create an empty data array
         let data = [];