Update dependency bazel_skylib to v1.8.0

Author: renovate[bot]

WORKSPACE

@@ -2,10 +2,10 @@ load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 http_archive(
     name = "bazel_skylib",
-    sha256 = "cd55a062e763b9349921f0f5db8c3933288dc8ba4f76dd9416aac68acee3cb94",
+    sha256 = "fa01292859726603e3cd3a0f3f29625e68f4d2b165647c72908045027473e933",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.5.0/bazel-skylib-1.5.0.tar.gz",
-        "https://github.com/bazelbuild/bazel-skylib/releases/download/1.5.0/bazel-skylib-1.5.0.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.8.0/bazel-skylib-1.8.0.tar.gz",
+        "https://github.com/bazelbuild/bazel-skylib/releases/download/1.8.0/bazel-skylib-1.8.0.tar.gz",
     ],
 )