fix: add missing endpoint url path to request and make image non-root

[tvcsantos]

Add missing relative path to request URL path.

The path to the azure API can be behing a URL that contains a relative prefix and not only just the host. Added the missing part to the request.

Also made the image run as non-root user, since it is not really needed to run as root and moreover in some contexts it is required to run images as non-root and is enforced by policies.

Upated the build script to use buildx instead