test docker and docker_image directly

testing/resources/docker_hooks_repo/.pre-commit-hooks.yaml

@@ -1,17 +0,0 @@
--   id: docker-hook
-    name: Docker test hook
-    entry: echo
-    language: docker
-    files: \.txt$
-
--   id: docker-hook-arg
-    name: Docker test hook
-    entry: echo -n
-    language: docker
-    files: \.txt$
-
--   id: docker-hook-failing
-    name: Docker test hook with nonzero exit code
-    entry: bork
-    language: docker
-    files: \.txt$

testing/resources/docker_hooks_repo/Dockerfile

@@ -1,3 +0,0 @@
-FROM ubuntu:focal
-
-CMD ["echo", "This is overwritten by the .pre-commit-hooks.yaml 'entry'"]

testing/resources/docker_image_hooks_repo/.pre-commit-hooks.yaml

@@ -1,8 +0,0 @@
--   id: echo-entrypoint
-    name: echo (via --entrypoint)
-    language: docker_image
-    entry: --entrypoint echo ubuntu:focal
--   id: echo-cmd
-    name: echo (via cmd)
-    language: docker_image
-    entry: ubuntu:focal echo