Use rules_shell

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 114cb06..4955620 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -25,6 +25,19 @@
 bazel_skylib_workspace()
 
 http_archive(
+    name = "rules_shell",
+    sha256 = "410e8ff32e018b9efd2743507e7595c26e2628567c42224411ff533b57d27c28",
+    strip_prefix = "rules_shell-0.2.0",
+    url = "https://github.com/bazelbuild/rules_shell/releases/download/v0.2.0/rules_shell-v0.2.0.tar.gz",
+)
+
+load("@rules_shell//shell:repositories.bzl", "rules_shell_dependencies", "rules_shell_toolchains")
+
+rules_shell_dependencies()
+
+rules_shell_toolchains()
+
+http_archive(
     name = "rules_testing",
     sha256 = "02c62574631876a4e3b02a1820cb51167bb9cdcdea2381b2fa9d9b8b11c407c4",
     strip_prefix = "rules_testing-0.6.0",