Fix name of profile data file

Author: andrewdavidmackenzie

.github/workflows/rust.yml

@@ -49,7 +49,7 @@ jobs:
         cargo install grcov
         rustup component add llvm-tools-preview
         echo RUSTFLAGS="-Zinstrument-coverage" >> "$GITHUB_ENV"
-        echo LLVM_PROFILE_FILE="flow-%p-%m.profraw" >> "$GITHUB_ENV"
+        echo LLVM_PROFILE_FILE="libproc-%p-%m.profraw" >> "$GITHUB_ENV"
 
     - name: Run Tests
       if: matrix.os != 'macos-11'