vlc-debian-stable: move to debian buster

Move to debian new stable:
- move to videolan-base-buster as base image
- add missing qt5 dev packages
- buster nasm version seems to be correct (2.14)

Notes:
- extra/tools should be used because protoc does not have the correct
  version in debian buster
- contrib should be used as well (especially for medialib)
1 job for master in 2 minutes and 47 seconds (queued for 1 second)
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passed #290260
build

00:02:47