fix: Pin crc-fast to 1.3.0 to avoid unstable feature requirements

The crc-fast crate version 1.6.0+ requires unstable Rust features
(stdarch_x86_avx512) which causes build failures in CI.

This commit:
- Pins crc-fast to =1.3.0 (last stable version without unstable features)
- Updates Cargo.lock accordingly (downgrades from 1.6.0 -> 1.3.0)
- Adds crc-fast to cargo-machete ignored list (it's a transitive dependency)
- Fixes warning in simple_scheduler.rs about unused Result from worker_lease.release()

Fixes the following CI failures:
- coverage/ (Nix build failure)
- publish-image/ (Docker image build failure)
- asan-ubuntu-24/ (ASAN test failure)

All failures were due to:
error[E0658]: use of unstable library feature `stdarch_x86_avx512`
See: rust-lang/rust#111137

Author: MarcusSorealheis

Cargo.lock

@@ -13,6 +13,9 @@ name = "nativelink"
 rust-version = "1.87.0"
 version = "0.7.6"
 
+[package.metadata.cargo-machete]
+ignored = ["crc-fast"]
+
 [profile.release]
 lto = true
 
@@ -74,6 +77,10 @@ tonic = { version = "0.13.0", features = [
 tower = { version = "0.5.2", default-features = false }
 tracing = { version = "0.1.41", default-features = false }
 
+# Pin crc-fast to avoid unstable features in 1.6.0+
+# See: https://github.com/rust-lang/rust/issues/111137
+crc-fast = { version = "=1.3.0", default-features = false }
+
 [workspace.cargo-features-manager.keep]
 async-lock = ["std"]
 aws-sdk-s3 = ["rt-tokio"]

Cargo.toml

@@ -373,11 +373,17 @@ impl SimpleScheduler {
                                             return Ok(());
                                         }
                                         // Release worker lease and return error
-                                        let _ = worker_lease
+                                        if let Err(release_err) = worker_lease
                                             .release(
                                                 nativelink_crio_worker_pool::WorkerOutcome::Failed,
                                             )
-                                            .await;
+                                            .await
+                                        {
+                                            tracing::warn!(
+                                                ?release_err,
+                                                "Failed to release worker lease after assignment failure"
+                                            );
+                                        }
                                         return Err(err);
                                     }