treewide: bump bazel to 8.3.1

This also bumps bazel_skylib, as it uses deprecated functionality.

Change-Id: I26d665967c14e5b3a437a3322f065ae1e2e63d9e
Reviewed-on: https://review.monogon.dev/c/monogon/+/4383
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
diff --git a/third_party/nix/pkgs/bazel/default.nix b/third_party/nix/pkgs/bazel/default.nix
index 0b6ba7e..c181db3 100644
--- a/third_party/nix/pkgs/bazel/default.nix
+++ b/third_party/nix/pkgs/bazel/default.nix
@@ -2,8 +2,8 @@
 stdenv.mkDerivation {
   name = "bazel";
   src = builtins.fetchurl {
-    url = "https://github.com/bazelbuild/bazel/releases/download/8.1.0/bazel-8.1.0-linux-x86_64";
-    sha256 = "19dwgh631d6c1m4ds1b1b3pbz18zm5i0x8bggjgsc04fyljfbfml";
+    url = "https://github.com/bazelbuild/bazel/releases/download/8.3.1/bazel-8.3.1-linux-x86_64";
+    sha256 = "0k3067d06b8160day48afskr42c41bz0qgb3pk9mjpr4hj57w90p";
   };
   unpackPhase = ''
     true