Update to alpine v3.12

What does this MR do?

Update to alpine v3.12

Why was this MR needed?

3.11 changelog: https://alpinelinux.org/posts/Alpine-3.11.0-released.html

3.11 changelog: https://alpinelinux.org/posts/Alpine-3.11.0-released.html

The biggest change that might cause problems is:

Python 2 is deprecated. Majority of Python 2 packages was removed and will be completely removed in next release`

3.12 changelog: https://alpinelinux.org/posts/Alpine-3.12.0-released.html

The biggest change that might cause problems is:

There is no longer a python package providing python2. You need to explicitly install python2 or python3. Additionally, as part of the ongoing work to remove python2, many python2 modules have been removed.

closes #26424 (closed)