Remove commented global augmentation code.

Global augmentation in TypeScript is still troublesome. In particular, it's difficult to exclude (and therefore difficult to avoid compile errors) if it's available in a project or `node_modules`, even if not imported directly:

- microsoft/TypeScript#37053
- #148

src/clipboard-polyfill/entries/es5/overwrite-globals.promise.ts

@@ -7,8 +7,4 @@ import { PromisePolyfillConstructor } from "../../promise/polyfill";
 
 import "./overwrite-globals";
 
-// declare global {
-//   // rome-ignore lint/suspicious/noShadowRestrictedNames: This is where we export `Promise`.
-//   var Promise: PromiseConstructor;
-// }
 (window as any).Promise = PromisePolyfillConstructor;

src/clipboard-polyfill/entries/es5/overwrite-globals.ts

@@ -2,14 +2,6 @@ import { readText, writeText } from "../../implementations/text";
 import { read, write } from "../../implementations/blob";
 import { ClipboardItemPolyfill } from "../../ClipboardItem/ClipboardItemPolyfill";
 
-// declare global {
-//   // const ClipboardItem: ClipboardItemConstructor;
-//   interface Window {
-//     ClipboardItem: ClipboardItemConstructor;
-//   }
-//   interface Clipboard extends ClipboardInterface {}
-// }
-
 // Create the `navigator.clipboard` object if it doesn't exist.
 if (!navigator.clipboard) {
   (navigator as any).clipboard = {};