use import-from over import-require (microsoft#166848)

fyi @hediet the latter doens't work for ESM

Author: jrieken

src/vs/editor/test/common/model/bracketPairColorizer/combineTextEditInfos.test.ts

@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import assert = require('assert');
+import * as assert from 'assert';
 import { ISingleEditOperation } from 'vs/editor/common/core/editOperation';
 import { Range } from 'vs/editor/common/core/range';
 import { TextEditInfo } from 'vs/editor/common/model/bracketPairsTextModelPart/bracketPairsTree/beforeEditPositionMapper';

src/vs/editor/test/node/diffing/diffing.test.ts

@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import assert = require('assert');
+import * as assert from 'assert';
 import { readdirSync, readFileSync, existsSync, writeFileSync } from 'fs';
 import { join, resolve } from 'path';
 import { FileAccess } from 'vs/base/common/network';