ci: update base OS from 20.04 to 22.04

[rst0git]

This pull request updates the base OS image used with GitHub actions from Ubuntu 20.04 to 22.04.

[rst0git]

@avagin I've rebased this pull request on top of https://github.com/checkpoint-restore/criu/pull/2320; without this patch zdtm/static/maps00 fails on Alpine and Arch Linux with the following error:

========================= Run zdtm/static/maps00 in h ==========================
Start test
./maps00 --pidfile=maps00.pid --outfile=maps00.out --filename=maps00.test
Run criu dump
=[log]=> dump/zdtm/static/maps00/62/1/dump.log
------------------------ grep Error ------------------------
(00.000000) CRIU run id = 0xf00001db0000003f
(00.000030) Version: 3.18 (gitid 0)
(00.000035) Running on 15be25e88600 Linux 6.5.0-1016-azure #16~22.04.1-Ubuntu SMP Fri Feb 16 15:42:02 UTC 2024 x86_64
(00.000038) Warn  (criu/kerndat.c:1195): $XDG_RUNTIME_DIR not set. Cannot find location for kerndat file
(00.008398) cpu: fpu: AVX registers                    xstate_offsets    576 / 576    xstate_sizes    256 / 256
(00.008514) Effective capability 12 missing
(00.009199) Found mmap_min_addr 0x10000
(00.009212) files stat: fs/nr_open 1048576
(00.009215) Warn  (criu/kerndat.c:1195): $XDG_RUNTIME_DIR not set. Cannot find location for kerndat file
(00.012140) Handling VMA with the following smaps entry: 7fec7315d000-7fec73160000 rw-p 00000000 00:00 0
(00.012152) Handling VMA with the following smaps entry: 7fec73160000-7fec73184000 r--p 00000000 08:11 4160986                    /usr/lib/libc.so.6
(00.012163) Failed to open map_files/7fec73160000-7fec73184000, try to go via [/usr/lib/libc.so.6] path
(00.012182) mnt: Path `/usr/lib/libc.so.6' resolved to `./' mountpoint
(00.012185) Error (criu/proc_parse.c:390): Failed to resolve mapping 7fec73160000 filename
(00.012192) Error (criu/proc_parse.c:704): Can't open 62's mapfile link 7fec73160000: Operation not permitted
(00.012198) Error (criu/cr-dump.c:1569): Collect mappings (pid: 62) failed with -1
(00.012256) net: Unlock network
(00.012260) Unfreezing tasks into 1
(00.012263) \tUnseizing 62 into 1
(00.012277) Error (criu/cr-dump.c:2104): Dumping FAILED.
------------------------ ERROR OVER ------------------------

[avagin]

Merged. Thanks