Add the changedFiles key and update logic in labeler

__tests__/fixtures/only_pdfs.yml

@@ -1,2 +1,3 @@
 touched-a-pdf-file:
-  - any: ['*.pdf']
+  - changed-files:
+    - any: ['*.pdf']

__tests__/labeler.test.ts

@@ -10,7 +10,7 @@ beforeAll(() => {
   });
 });
 
-const matchConfig = [{any: ['*.txt']}];
+const matchConfig = [{changedFiles: {any: ['*.txt']}}];
 
 describe('checkGlobs', () => {
   it('returns true when our pattern does match changed files', () => {