[LTP] [RFC][PATCH 1/1] ci: Ubuntu xenial -> bionic

[Petr Vorel]

Hi Cyril,

gently ping for ack.

NOTE: if we accept it, I need also to update doc/supported-kernel-libc-versions.txt:

-| Ubuntu 16.04 LTS xenial      | 4.4    | 2.23  | 5.3.1 | -
-| Debian 9 stretch (oldstable) | 4.9.30 | 2.24  | 6.3.0 | 3.8
+| Debian 9 stretch (oldstable) | 4.9.30 | 2.24  | 6.3.0 | 3.8
+| Ubuntu 16.04 LTS xenial      | 4.15   | 2.27  | 7.3.0 | -

Kind regards,
Petr