Remove unused, empty //rules:bins filegroup, allowing us to simplify distribution/BUILD (#359)

//rules:bins has not been used since 14f17ae7f71f347b5e720fca55e33df40bc4e5d5

Alternative to https://github.com/bazelbuild/bazel-skylib/pull/358
diff --git a/BUILD b/BUILD
index d61528f..fd7798b 100644
--- a/BUILD
+++ b/BUILD
@@ -75,10 +75,3 @@
         "//toolchains/unittest:distribution",
     ] + glob(["*.bzl"]),
 )
-
-filegroup(
-    name = "bins",
-    srcs = [
-        "//rules:bins",
-    ],
-)
diff --git a/distribution/BUILD b/distribution/BUILD
index ba903aa..8a9b1e7 100644
--- a/distribution/BUILD
+++ b/distribution/BUILD
@@ -6,37 +6,15 @@
     default_visibility = ["//visibility:private"],
 )
 
-pkg_tar(
-    name = "srcs",
-    srcs = ["//:distribution"],
-    mode = "0444",
-    # Make it owned by root so it does not have the uid of the CI robot.
-    owner = "0.0",
-    package_dir = "",
-    strip_prefix = ".",
-)
-
-pkg_tar(
-    name = "bins",
-    srcs = ["//:bins"],
-    mode = "0555",
-    # Make it owned by root so it does not have the uid of the CI robot.
-    owner = "0.0",
-    package_dir = "",
-    strip_prefix = ".",
-)
-
 # Build the artifact to put on the github release page.
 pkg_tar(
     name = "bazel-skylib-%s" % version,
+    srcs = ["//:distribution"],
     extension = "tar.gz",
+    mode = "0644",
     # Make it owned by root so it does not have the uid of the CI robot.
     owner = "0.0",
     strip_prefix = ".",
-    deps = [
-        ":bins.tar",
-        ":srcs.tar",
-    ],
 )
 
 print_rel_notes(
diff --git a/rules/BUILD b/rules/BUILD
index 6bb55b9..f7017bb 100644
--- a/rules/BUILD
+++ b/rules/BUILD
@@ -68,14 +68,6 @@
     ],
 )
 
-filegroup(
-    name = "bins",
-    srcs = glob(["*.sh"]),
-    visibility = [
-        "//:__pkg__",
-    ],
-)
-
 # export bzl files for the documentation
 exports_files(
     glob(["*.bzl"]),