Mitigate 429 Too Many Requests (https://github.com/reproducible-containers/repro-get/releases/latest/download/VERSION/)

[AkihiroSuda]

Run repro-get --distro=debian dockerfile generate . debian:bullseye-20211220 gcc build-essential
time="2023-01-1[4](https://github.com/reproducible-containers/repro-get/actions/runs/3919656008/jobs/6700793649#step:8:5)T18:04:2[5](https://github.com/reproducible-containers/repro-get/actions/runs/3919656008/jobs/6700793649#step:8:6)Z" level=warning msg="The current version \"v0.2.1-15-gffafc69\" does not seem downloadable, falling back to the latest version" error="non-downloadable version: \"v0.2.1-15-gffafc69\""
time="2023-01-14T18:04:25Z" level=fatal msg="failed to detect the latest version: failed to detect the latest version: expected HTTP status 200 for \"[https://github.com/reproducible-containers/repro-get/releases/latest/download/VERSION\](https://github.com/reproducible-containers/repro-get/releases/latest/download/VERSION/)", got 429 Too Many Requests"