Update the container image to openSUSE Leap 16

[nodeg]

Description

The docker container is still build upon openSUSE Leap 15.5. It should be updated to Leap 16 for example.

uyuni-docs-helper/image/Dockerfile

Line 1 in 3a39e52

FROM opensuse/leap:15.5

Tasks

• bump the version to openSUSE Leap 16
• verify that all installation steps in the dockerfile still work
• if not, make the necessary adjustments

Links

• https://github.com/nvm-sh/nvm#installing-in-docker