Fixed sample-config to proper yaml formatting

* Fixed yaml formatting
    * bumped version in sample config :)

pre_commit/commands/sample_config.py

@@ -3,11 +3,13 @@
 # significantly faster than https:// or http://).  For now, periodically
 # manually updating the revision is fine.
 SAMPLE_CONFIG = '''\
+---
+
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.2.0
+    rev: v3.3.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer