cldrjs: make directory structure match source (#40664)

Move supplemental files into cldr/ subdirectory.

Also make the test reference supplemental instead of relying on it being
in the global namespace.

types/cldrjs/OTHER_FILES.txt

@@ -1 +1 @@
-cldr.js-event.d.ts
+cldr/event.d.ts

types/cldrjs/test/supplemental.ts

@@ -1,5 +1,5 @@
-
-
+import * as Cldr from "cldrjs";
+import "cldrjs/cldr/supplemental";
 
 const myCldr = new Cldr("en");
 

types/cldrjs/tsconfig.json

@@ -19,9 +19,9 @@
     },
     "files": [
         "index.d.ts",
-        "cldr.js-supplemental.d.ts",
+        "cldr/supplemental.d.ts",
         "test/index.ts",
         "test/event.ts",
         "test/supplemental.ts"
     ]
-}
+}