Add .cache folder to default exclude list (#1479)

To avoid false-positive results from users did not add .cache folder
to their .gitignore file, include it in the implicit exclude_paths.

Fixes: #1463

Author: ssbarnea

.ansible-lint

@@ -1,5 +1,6 @@
 # .ansible-lint
 exclude_paths:
+- .cache/  # implicit unless exclude_paths is defined in config
 - .github/
 # parseable: true
 # quiet: true

src/ansiblelint/cli.py

@@ -314,7 +314,7 @@ def merge_config(file_config: Dict[Any, Any], cli_config: Namespace) -> Namespac
     )
     # maps lists to their default config values
     lists_map = {
-        'exclude_paths': [],
+        'exclude_paths': [".cache"],
         'rulesdir': [],
         'skip_list': [],
         'tags': [],