Update firestore.d.ts

Author: milaGGL

handwritten/firestore/types/firestore.d.ts

@@ -10621,9 +10621,9 @@ declare namespace FirebaseFirestore {
      * // Return "Active" if field "status" is 1, "Pending" if field "status" is 2,
      * // and default to "Unknown" if none of the conditions are true.
      * switchOn(
-     *   equal(field("status"), 1), "Active",
-     *   equal(field("status"), 2), "Pending",
-     *   "Unknown"
+     *   equal(field("status"), 1), constant("Active"),
+     *   equal(field("status"), 2), constant("Pending"),
+     *   constant("Unknown")
      * )
      * ```
      *