chore(pkglint): ignore cdk.out and .cdk.staging (#8709)

Those directories can contain `package.json` files coming for bundled
assets (integ tests) that should never be linted.


----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

tools/pkglint/lib/packagejson.ts

@@ -2,6 +2,9 @@ import * as colors from 'colors/safe';
 import * as fs from 'fs-extra';
 import * as path from 'path';
 
+// do not descend into these directories when searching for `package.json` files.
+export const PKGLINT_IGNORES = ['node_modules', 'cdk.out', '.cdk.staging'];
+
 /**
  * Return all package JSONs in the root directory
  */
@@ -24,8 +27,8 @@ export function findPackageJsons(root: string): PackageJson[] {
         ret.push(new PackageJson(fullPath));
       }
 
-      // Recurse into all dirs except node_modules
-      if (file !== 'node_modules' && (fs.lstatSync(fullPath)).isDirectory()) {
+      // Recurse into all dirs except ignored dirs
+      if (!PKGLINT_IGNORES.includes(file) && (fs.lstatSync(fullPath)).isDirectory()) {
         recurse(fullPath);
       }
     }

tools/pkglint/lib/util.ts

@@ -1,6 +1,6 @@
 import * as fs from 'fs';
 import * as path from 'path';
-import { PackageJson } from "./packagejson";
+import { PackageJson, PKGLINT_IGNORES } from "./packagejson";
 
 /**
  * Expect a particular JSON key to be a given value
@@ -168,7 +168,7 @@ export function* findInnerPackages(dir: string): IterableIterator<string> {
       if (e.code !== 'ENOENT') { throw e; }
       continue;
     }
-    if (fname === 'node_modules') { continue; }
+    if (PKGLINT_IGNORES.includes(fname)) { continue; }
 
     if (fs.existsSync(path.join(dir, fname, 'package.json'))) {
       yield path.join(dir, fname);