[v11.3.x] BarChart: Skip formatting null-valued ticks (#95094)

BarChart: Skip formatting null-valued ticks (#94935)

Co-authored-by: Ihor Yeromin <yeryomin.igor@gmail.com>
(cherry picked from commit 594e9b1b73)

Co-authored-by: Leon Sorokin <leeoniya@gmail.com>

packages/grafana-ui/src/components/uPlot/config/UPlotAxisBuilder.ts

@@ -168,7 +168,13 @@ export class UPlotAxisBuilder extends PlotConfigBuilder<AxisProps, Axis> {
     } else if (formatValue) {
       config.values = (u: uPlot, splits, axisIdx, tickSpace, tickIncr) => {
         let decimals = guessDecimals(roundDecimals(tickIncr, 6));
-        return splits.map((v) => formatValue!(v, decimals > 0 ? decimals : undefined));
+        return splits.map((v) => {
+          if (v == null) {
+            return null;
+          } else {
+            return formatValue!(v, decimals > 0 ? decimals : undefined);
+          }
+        });
       };
     }