[INFO] cloning repository https://github.com/swkfn/rust-slack-bot-sample
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/swkfn/rust-slack-bot-sample" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fswkfn%2Frust-slack-bot-sample", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fswkfn%2Frust-slack-bot-sample'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e3fb8e95884e8a8e3e6c802107be566145023128
[INFO] checking swkfn/rust-slack-bot-sample against master#0f353363965ebf05e0757f7679c800b39c51a07e for pr-144896
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fswkfn%2Frust-slack-bot-sample" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] error: failed to write new configuration file /workspace/builds/worker-5-tc1/source/.git/config.lock
[INFO] [stderr] fatal: could not set 'core.repositoryformatversion' to '0'


failed to checkout https://github.com/swkfn/rust-slack-bot-sample

Caused by:
    command failed: exit status: 128