rec docs: Document how to disable allow_notify_for

[dasJ]

Short description

Checklist

I have:

• read the CONTRIBUTING.md document
• read and accepted the Developer Certificate of Origin document, including the AI Policy, and added a "Signed-off-by" to my commits
• 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 19837572585

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 32 unchanged lines in 8 files lost coverage.
• Overall coverage increased (+0.02%) to 73.108%

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Files with Coverage Reduction	New Missed Lines	%
pdns/dnsdistdist/dnsdist-tcp.cc	1	77.3%
pdns/recursordist/aggressive_nsec.cc	2	66.54%
pdns/rcpgenerator.cc	3	90.95%
pdns/recursordist/test-syncres_cc2.cc	3	89.12%
pdns/misc.cc	4	61.5%
pdns/recursordist/rec-tcpout.cc	5	73.23%
pdns/recursordist/test-syncres_cc1.cc	5	90.3%
pdns/dnsdistdist/dnsdist-carbon.cc	9	62.01%

Totals
Change from base Build 19826378156:	0.02%
Covered Lines:	128115
Relevant Lines:	164535

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💛 - Coveralls

[omoerbeek]

Thanks for the PR. IMO the actual problem is that it isn't documented the matching is done by suffix match. Can you reformulate? After that it should be clear that dot matches all names.