Fix canary to use latest dependency versions from PRs

The canary was using stale dependency versions from committed Cargo.lock
files instead of the versions specified in PRs. This caused the canary
to miss the crc-fast 1.4 SIGILL issue.

Solution: Delete workspace Cargo.lock files before running the canary to
force fresh dependency resolution. This ensures the canary tests the exact
dependency versions from the PR.

Fixes #3981

Author: vcjana

tools/ci-scripts/run-canary

@@ -15,6 +15,13 @@ export RUST_LOG=debug
 
 SDK_PATH="$(pwd)/aws-sdk/sdk"
 
+# Delete workspace Cargo.lock files to ensure fresh dependency resolution.
+# This ensures the canary uses the exact dependency versions from the PR,
+# not stale versions from a committed lock file.
+# See: https://github.com/smithy-lang/smithy-rs/issues/3981
+rm -f smithy-rs/rust-runtime/Cargo.lock
+rm -f smithy-rs/aws/rust-runtime/Cargo.lock
+
 cd smithy-rs/tools/ci-cdk/canary-runner
 aws s3 cp s3://"${CANARY_STACK_CDK_OUTPUTS_BUCKET_NAME}"/cdk-outputs.json .
 cargo run -- \