Merge branch 'test/mariadb-connector-c' into '2.11'

See merge request !26

Use mariadb-connector-c for RHEL 8+

See merge request !25

https://github.com/Icinga/icinga-packaging/issues/205

(cherry picked from commit a894a068)

7bf92e3d Use mariadb-connector-c for RHEL 8+
98704be6 Try excluding mysql-devel
a6d6aa46 Try setting BuildRequires to Requires
59f9680d Re-add BuildRequires
cc51938b Add script to remove mysql-devel
9bba7fb5 Add a sudo :(
e813ef63 ...and assume yes when removing mysql-devel
2716e965 Remove mysql-devel before the script
d04228d5 Remove remove mysql-devel instruction

Release 2.11.10-1

See merge request !23

Note: The release builds for this security update were prepared in a private
fork before publishing the release and were uploaded from there:
https://git.icinga.com/packaging/icinga2-2.12.5-2.11.10/raspbian-icinga2

Drop Fedora 31

See merge request !11

Drop Fedora 30

See merge request !10

Drop CentOS 6

See merge request !16

Drop Fedora 29

See merge request !9

Drop openSUSE 15.0

See merge request !12

Drop SLES 12.4

See merge request !13

Drop SLES 15.0

See merge request !14

Add support for SLES 12 SP 5

See merge request !1