Avoid error when using ticks in single-scale charts without specifying callback (#171)

Single-scale charts are radar and polar area.

Co-authored-by: Joel Liechti <52202086+Joelius300@users.noreply.github.com>

Author: ipax77

src/ChartJs.Blazor/Interop/TypeScript/ChartJsInterop.ts

@@ -246,6 +246,10 @@ class ChartJsInterop {
 
         if (config.options?.scale?.ticks) {
             config.options.scale.ticks.callback = this.getMethodHandler(<IMethodHandler>config.options.scale.ticks.callback, undefined);
+
+            if (!config.options.scale.ticks.callback) {
+                delete config.options.scale.ticks.callback; // undefined != deleted, Chart.js throws an error if it's undefined so we have to delete it
+            }
         }
     }