ci: Fixes parsing of MSRV (#2555)

* Fixes parsing of MSRV

* Pins half and errorchecks MSRV

Author: maddeleine

.github/workflows/ci.yml

@@ -54,10 +54,15 @@ jobs:
       - name: Evaluate definitions
         id: definitions
         run: |
-          export MSRV=$(rustup show | awk 'NF' | awk 'END{print $2}')
+          rustup show active-toolchain
+          export MSRV=$(rustup show active-toolchain | awk -F'-' '{print $1}')
+          if [ -z "$MSRV" ]; then
+            echo "Error: MSRV did not parse correctly"
+            exit 1
+          fi
           echo "msrv=$MSRV"
           echo "msrv=$MSRV" >> $GITHUB_OUTPUT
-          export RAW_VERSIONS="stable beta $RUST_NIGHTLY_TOOLCHAIN $MSRV"
+          export RAW_VERSIONS="stable beta $MSRV"
           export VERSIONS=$(echo $RAW_VERSIONS | jq -scR 'rtrimstr("\n")|split(" ")|.')
           echo "versions=$VERSIONS"
           echo "versions=$VERSIONS" >> $GITHUB_OUTPUT

quic/s2n-quic-bench/Cargo.toml

@@ -12,6 +12,7 @@ publish = false
 bytes = "1"
 criterion = { version = "0.5", features = ["html_reports"] }
 crossbeam-channel = { version = "0.5" }
+half = "=2.4.1" # Can be unpinned when we move to MSRV 1.81
 internet-checksum = "0.2"
 s2n-codec = { path = "../../common/s2n-codec", features = ["testing"] }
 s2n-quic-core = { path = "../s2n-quic-core", features = ["testing"] }