chore(deps): upgrade bazel-skylib to 1.8.1 (#3118)

With most recent bazel versions, older versions of rules_python started
spewing a lot of warnings due to us using `bazel-skylib` for copying
files around.

The only solution is to bump the bazel-skylib version.

Fixes #3113

---------

Co-authored-by: Richard Levasseur <richardlev@gmail.com>

CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b235989..abeb174 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -54,6 +54,9 @@
 
 {#v0-0-0-changed}
 ### Changed
+* (deps) (bzlmod) Upgraded to `bazel-skylib` version
+  [1.8.1](https://github.com/bazelbuild/bazel-skylib/releases/tag/1.8.1)
+  to remove deprecation warnings.
 * (gazelle) For package mode, resolve dependencies when imports are relative
   to the package path. This is enabled via the
   `# gazelle:python_experimental_allow_relative_imports` true directive ({gh-issue}`2203`).

MODULE.bazel

diff --git a/MODULE.bazel b/MODULE.bazel
index 9db287d..b8d8c16 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -5,7 +5,7 @@
 )
 
 bazel_dep(name = "bazel_features", version = "1.21.0")
-bazel_dep(name = "bazel_skylib", version = "1.7.1")
+bazel_dep(name = "bazel_skylib", version = "1.8.1")
 bazel_dep(name = "rules_cc", version = "0.0.16")
 bazel_dep(name = "platforms", version = "0.0.11")