* feat: hardened authelia binaries
This change ensures that all Authelia binaries which are compiled and distributed are hardened with the following standards:
* RELRO
* Stack canary
* NX
* PIE/ASLR
* Stripped RPATH AND RUNPATH
* Stripped Symbols
* Fortify
The musl variants currently [do not support Fortify](https://wiki.musl-libc.org/future-ideas.html#Fortify).
* refactor: docker pull for authelia/crossbuild in background