The binary included in the [url=https://archlinuxarm.org/packages/aarch64/gitlab-runner]gitlab-runner[/url] package for aarch64 is not the one for the correct architecture, it is the one for x86-64:
[code]
% file usr/bin/gitlab-runner
usr/bin/gitlab-runner: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=2e0681b30c7729a6b540f1f24c21134e34bf9743, not stripped
[/code]