Add comment about protocol-runner path

.drone.yml

@@ -259,6 +259,8 @@ steps:
     - mv usr/local/etc/tezedge-data/tezedge_27708_2021-05-26T12:45:48.076277293+00:00/_data /tmp/tezedge_developer/data
     - rust_libs=$(echo "`rustup show home`/toolchains/`rustup show active-toolchain | tr " " "\n" | head -1`/lib")
     - export LD_LIBRARY_PATH="$${BUILD_ARTIFACTS_PATH}/build_files/ffi:$rust_libs"
+    # light-node reads the path of `protocol-runner` from the config file, even if provided as argument.
+    # Copy the `protocol-runner` binary to the path specified in the config file.
     - mkdir -p target/release
     - cp $${BUILD_ARTIFACTS_PATH}/build_files/protocol-runner target/release/
     - $${BUILD_ARTIFACTS_PATH}/build_files/light-node replay --target-path=/tmp/replay --config-file "$${BUILD_ARTIFACTS_PATH}/build_files/tezedge/tezedge_drone.config" --network=mainnet --to-block BLUP2BFdCq4qkFh6Sry7AGwa21D5hJUv8yLyWnNVLMwnLgF8JnF --one-context --tezos-data-dir=/tmp/tezedge_developer/data --identity-file "$${BUILD_ARTIFACTS_PATH}/build_files/identities/identity_6.json" --bootstrap-db-path=bootstrap_db