Switch to accessibility insights's version of these tools (#603)

* Switch to accessibility insights's version of these tools

* auto-add files meeting strict checks

strict-null-checks/config.js

@@ -0,0 +1,11 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+const path = require("path");
+const repoRoot = path.join(__dirname, "../").replace(/\\/g, "/");
+
+module.exports = {
+  repoRoot: repoRoot,
+  srcRoot: `${repoRoot}/src`,
+  targetTsconfig: "tsconfig.strict.json",
+  skippedFiles: new Set([]),
+};