dnsdist-1.9.x: Backport 14570 - Return a valid unix timestamp for Dynamic Block's until

[rgacogne]

Short description

Backport of #14570 to dnsdist-1.9.x.

We internally use a timestamp obtained via CLOCK_MONOTONIC which is quite useless to an external observer, so convert it to a normal unix timestamp in the Lua accessor.

Checklist

I have:

• read the CONTRIBUTING.md document
• compiled this code
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)
• checked that this code was merged to master

[coveralls]

Pull Request Test Coverage Report for Build 10774948845

Details

• 2 of 19 (10.53%) changed or added relevant lines in 1 file are covered.
• 7 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.02%) to 55.773%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pdns/dnsdist-lua-inspection.cc	2	19	10.53%

Files with Coverage Reduction	New Missed Lines	%
pdns/dnscrypt.cc	1	68.07%
pdns/iputils.hh	2	75.0%
pdns/misc.cc	2	40.18%
pdns/dnsdistdist/dnsdist-async.cc	2	82.21%

Totals
Change from base Build 9987810845:	-0.02%
Covered Lines:	47997
Relevant Lines:	65527

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💛 - Coveralls