💄(react) make DatePicker placeholders uppercase

This was a feedback from the QA.

.changeset/calm-steaks-agree.md

@@ -0,0 +1,5 @@
+---
+"@openfun/cunningham-react": minor
+---
+
+make DatePicker placeholders uppercase

packages/react/src/components/Forms/DatePicker/DateField.tsx

@@ -37,7 +37,7 @@ const DateSegmentInput = ({
           (currentSegment.type === "literal" && previousSegment?.isPlaceholder),
       })}
     >
-      {currentSegment.text}
+      {currentSegment.text?.toUpperCase()}
     </div>
   );
 };

packages/react/src/components/Forms/DatePicker/DatePicker.spec.tsx

@@ -420,7 +420,7 @@ describe("<DatePicker/>", () => {
 
     // Date field's value should be set to a placeholder value.
     const dateFieldContent = screen.getByRole("presentation").textContent;
-    expect(dateFieldContent).eq("mm/dd/yyyy");
+    expect(dateFieldContent).eq("MM/DD/YYYY");
 
     const isGridCellSelected = screen
       .getByRole("gridcell", { name: "24" })!

packages/react/src/components/Forms/DatePicker/DateRangePicker.spec.tsx

@@ -743,8 +743,8 @@ describe("<DateRangePicker/>", () => {
 
     // Date field's value should be set to a placeholder value.
     const [startInput, endInput] = await screen.queryAllByRole("presentation");
-    expect(startInput.textContent).eq("mm/dd/yyyy");
+    expect(startInput.textContent).eq("MM/DD/YYYY");
-    expect(endInput.textContent).eq("mm/dd/yyyy");
+    expect(endInput.textContent).eq("MM/DD/YYYY");
 
     const startGridCell = screen.getByRole("gridcell", {
       name: "25",