[FIX] chart: tooltip has wrong format for date chart

The tooltip doesn't have the same format as the date format of the
cells of the chart. We were missing the `tooltipFormat` option.

closes #7226

Task: 5126261
Signed-off-by: Rémi Rahir (rar) <rar@odoo.com>

Author: hokolomopo

src/helpers/chart_date.ts

@@ -64,6 +64,7 @@ export function getChartTimeOptions(
     parser: luxonFormat,
     displayFormats,
     unit: timeUnit ?? false,
+    tooltipFormat: luxonFormat,
   };
 }
 

tests/figures/chart/__snapshots__/chart_plugin.test.ts.snap

@@ -201,6 +201,7 @@ exports[`Linear/Time charts snapshot test of chartJS configuration for date char
               "day": "M/d/yyyy",
             },
             "parser": "M/d/yyyy",
+            "tooltipFormat": "M/d/yyyy",
             "unit": "day",
           },
           "type": "time",

tests/figures/chart/chart_plugin.test.ts

@@ -1908,12 +1908,14 @@ describe("Linear/Time charts", () => {
       },
       chartId
     );
-    let chart = (model.getters.getChartRuntime(chartId) as LineChartRuntime).chartJsConfig;
-    expect(chart.options?.scales?.x?.type).toEqual("time");
-
-    updateChart(model, chartId, { type: "bar" });
-    model.getters.getChartRuntime(chartId)!;
-    expect(chart.options?.scales?.x?.type).toEqual("time");
+    const scale = (model.getters.getChartRuntime(chartId) as any).chartJsConfig.options.scales.x;
+    expect(scale.type).toEqual("time");
+    expect(scale.time).toEqual({
+      displayFormats: { day: "M/d/yyyy" }, // luxon format
+      parser: "M/d/yyyy",
+      tooltipFormat: "M/d/yyyy",
+      unit: "day",
+    });
   });
 
   test("time axis for line/bar chart with formulas w/ date format as labels", () => {