CI: enable parallel tests (for x86_64, at least)

[IvanNardi]

TODO: enable parallel tests when using docker with no-x86_64 archs.

When I tried the obviuos solutions:

NDPI_FORCE_PARALLEL_UTESTS=1 NDPI_SKIP_PARALLEL_BAR=1 make check VERBOSE=1

I got:

Run configuration "caches_cfg" [--cfg=lru.ookla.size,0 --cfg=lru.msteams.ttl,1]
ookla.pcap  /bin/sh: 1: run_single_pcap: not found
teams.pcap  /bin/sh: 1: run_single_pcap: not found
Run configuration "caches_global" [--cfg=lru.ookla.scope,1 --cfg=lru.bittorrent.scope,1 --cfg=lru.stun.scope,1 --cfg=lru.tls_cert.scope,1 --cfg=lru.mining.scope,1 --cfg=lru.msteams.scope,1 --cfg=lru.stun_zoom.scope,1]
bittorrent.pcap /bin/sh: 1: run_single_pcap: not found
lru_ipv6_caches.pcapng  /bin/sh: 1: run_single_pcap: not found
mining.pcapng   /bin/sh: 1: run_single_pcap: not found
...

[sonarcloud[bot]]

Quality Gate passed

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0 New issues
0 Accepted issues

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