Fix wget with http_proxy on busybox x86_64
Fix wget with http_proxy on busybox x86_64

On busybox x86_64, busybox's wget is compiled with http proxy support but without wgetrc support

This commit fills an environment file instead of writing a wgetrc file
QuentinPerez/scaleway-cli,QuentinPerez/scaleway-cli,QuentinPerez/scaleway-cli