Dockerfile: update xx to 1.1

[thaJeztah]

splitting up #3383 (where we're debugging some issues with cross compiles); moving this to a separate PR so that we can test/merge some changes in isolation.

- How to verify it

- Description for the changelog

- A picture of a cute animal (not mandatory but encouraged)

[codecov-commenter]

Codecov Report

Merging #3489 (40d8016) into master (87b8e57) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3489   +/-   ##
=======================================
  Coverage   59.01%   59.01%           
=======================================
  Files         284      284           
  Lines       23833    23833           
=======================================
  Hits        14066    14066           
  Misses       8908     8908           
  Partials      859      859           

[thaJeztah]

FTR, so the osusergo issue is indeed already present in current builds (so not new in #3383);

#37 399.9 /usr/bin/s390x-linux-gnu-ld: /tmp/go-link-800461440/000018.o: in function `mygetgrouplist':
#37 399.9 /usr/local/go/src/os/user/getgrouplist_unix.go:16: warning: Using 'getgrouplist' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking

[thaJeztah]

thx!

[thaJeztah]

We should fix this; or does xx also have a apt-get ? apt meant for "humans", and not meant for scripting (see the warning);

#54 [linux/amd64 build-buster 1/1] RUN xx-apt install --no-install-recommends -y libc6-dev libgcc-8-dev
#54 0.706 Hit:1 http://security.debian.org/debian-security buster/updates InRelease
#54 0.707 Hit:2 http://deb.debian.org/debian buster InRelease
#54 0.708 Hit:3 http://deb.debian.org/debian buster-updates InRelease
#54 2.149 Reading package lists...
#54 4.917 + apt  install --no-install-recommends -y libc6-dev libgcc-8-dev
#54 4.934 
#54 4.934 WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
#54 4.934 

[crazy-max]

Yes xx has xx-apt-get: tonistiigi/xx#40

[thaJeztah]

Yup, just found it; https://github.com/tonistiigi/xx/blob/v1.1.0/base/xx-apt#L58 😂

[thaJeztah]

opened #3491