Update blst to 0.3.11 (#4624)

## Proposed Changes

This PR updates `blst` to 0.3.11, which gives us _runtime detection of CPU features_ 🎉

Although [performance benchmarks](https://gist.github.com/michaelsproul/f759fa28dfa4003962507db34b439d6c) don't show a substantial detriment to running the `portable` build vs `modern`, in order to take things slowly I propose the following roll-out strategy:

- Keep both `modern` and `portable` builds for releases/Docker images.
- Run the `portable` build on half of SigP's infrastructure to monitor for performance deficits.
- Listen out for user issues with the `portable` builds (e.g. SIGILLs from misdetected hardware).
- Make the `portable` build the default and remove the `modern` build from our release binaries & Docker images.

Cargo.lock

@@ -732,14 +732,13 @@ dependencies = [
 
 [[package]]
 name = "blst"
-version = "0.3.10"
+version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a30d0edd9dd1c60ddb42b80341c7852f6f985279a5c1a83659dcb65899dec99"
+checksum = "c94087b935a822949d3291a9989ad2b2051ea141eda0fd4e478a75f6aa3e604b"
 dependencies = [
  "cc",
  "glob",
  "threadpool",
- "which",
  "zeroize",
 ]
 
@@ -8981,17 +8980,6 @@ dependencies = [
  "rustls-webpki 0.100.1",
 ]
 
-[[package]]
-name = "which"
-version = "4.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2441c784c52b289a054b7201fc93253e288f094e2f4be9058343127c4226a269"
-dependencies = [
- "either",
- "libc",
- "once_cell",
-]
-
 [[package]]
 name = "widestring"
 version = "0.4.3"

Makefile

@@ -207,7 +207,7 @@ arbitrary-fuzz:
 # Runs cargo audit (Audit Cargo.lock files for crates with security vulnerabilities reported to the RustSec Advisory Database)
 audit:
 	cargo install --force cargo-audit
-	cargo audit --ignore RUSTSEC-2020-0071
+	cargo audit --ignore RUSTSEC-2020-0071 --ignore RUSTSEC-2022-0093
 
 # Runs `cargo vendor` to make sure dependencies can be vendored for packaging, reproducibility and archival purpose.
 vendor: