Migrate to Bazelisk

This commit changes the Nix-side Bazel setup to Bazelisk which
decouples the Bazel version from what's available in the nix store.

This lets us more freely increment Bazel versions while still providing
the correct versions automatically.

A nice side effect of this is that we can finally remove the WORKSPACE
file.

This change has no effect on the Bazel versions that NativeLink supports
as clients. This is purely an internal build dependency change.

.bazelversion

@@ -1 +1 @@
-7.1.0
+7.1.2

MODULE.bazel

@@ -6,7 +6,7 @@ module(
 
 bazel_dep(name = "rules_cc", version = "0.0.9")
 bazel_dep(name = "platforms", version = "0.0.10")
-bazel_dep(name = "rules_python", version = "0.31.0")
+bazel_dep(name = "rules_python", version = "0.32.1")
 
 python = use_extension("@rules_python//python/extensions:python.bzl", "python")
 python.toolchain(
@@ -23,6 +23,18 @@ bazel_dep(name = "rules_rust", version = "0.44.0")
 rust = use_extension("@rules_rust//rust:extensions.bzl", "rust")
 rust.toolchain(
     edition = "2021",
+    sha256s = {
+        "2024-05-10/rustc-nightly-x86_64-unknown-linux-gnu.tar.xz": "34c251c59c99d68d13144ca00f7dd1af47227640ffdd00c6966342535a6c6f6b",
+        "2024-05-10/clippy-nightly-x86_64-unknown-linux-gnu.tar.xz": "cf705952dd0f4e8d9f6fd69bb3810370e7d8ac78cb96419a2883eee8f182c7fb",
+        "2024-05-10/cargo-nightly-x86_64-unknown-linux-gnu.tar.xz": "a96ec1120436493e018df070625e46764987d60e7293533fdbfdbca16967c81a",
+        "2024-05-10/llvm-tools-nightly-x86_64-unknown-linux-gnu.tar.xz": "bc134e14df374e7dc86fa726de75c7d145bc68be9476af5d395252345e41a45f",
+        "2024-05-10/rust-std-nightly-x86_64-unknown-linux-gnu.tar.xz": "878dacc66ead1a12ebc1c9996d4d4be40b8931b8dd6de55433d872f88399fe7d",
+        "2024-05-10/rustc-nightly-x86_64-apple-darwin.tar.xz": "8832320e438a1702571630e12d73194c964c8d21c8fe621cc8bed4ae0ce97625",
+        "2024-05-10/clippy-nightly-x86_64-apple-darwin.tar.xz": "80657ff2c67fe37469940e5983ec868c566b017bc1620f11a6a65e5f029ac42e",
+        "2024-05-10/cargo-nightly-x86_64-apple-darwin.tar.xz": "7390b4d229d9d3a8108c632939426021c12d63ae2681554386a344dd44c50e83",
+        "2024-05-10/llvm-tools-nightly-x86_64-apple-darwin.tar.xz": "b69cd7d16d6fcd78c26a5e78fb9a56fa4116f49d4ece7282253dd9b8fc276b04",
+        "2024-05-10/rust-std-nightly-x86_64-apple-darwin.tar.xz": "0e5f07efa6660c48ceaff776aa4616992a985b5d41247f79304fdaec231e63d2",
+    },
     versions = [
         "1.78.0",
         "nightly/2024-05-10",

flake.nix

@@ -229,7 +229,7 @@
           nativeBuildInputs = let
             bazel = pkgs.writeShellScriptBin "bazel" ''
               unset TMPDIR TMP
-              exec ${pkgs.bazel_7}/bin/bazel "$@"
+              exec ${pkgs.bazelisk}/bin/bazelisk "$@"
             '';
           in
             [