Add Honeypot HTTP Scan feed to Shadowserver parser

[monoidic]

This PR adds the Honeypot HTTP Scan feed to the Shadowserver parser, along with the related sample and test.

[codecov-commenter]

Codecov Report

Merging #2047 (b550d3b) into develop (9d4baa8) will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop    #2047      +/-   ##
===========================================
+ Coverage    75.98%   76.03%   +0.04%     
===========================================
  Files          429      429              
  Lines        23011    23036      +25     
  Branches      3062     3063       +1     
===========================================
+ Hits         17486    17516      +30     
+ Misses        4817     4814       -3     
+ Partials       708      706       -2     

Impacted Files	Coverage Δ
intelmq/bots/parsers/shadowserver/_config.py	98.73% <100.00%> (+1.45%)	⬆️
...ers/shadowserver/test_event4_honeypot_http_scan.py	100.00% <100.00%> (ø)
...q/tests/bots/outputs/sql/test_output_postgresql.py	86.95% <0.00%> (-0.19%)	⬇️
intelmq/tests/bots/outputs/smtp/test_output.py	100.00% <0.00%> (ø)
intelmq/bots/outputs/postgresql/output.py
intelmq/lib/bot.py	62.48% <0.00%> (+0.42%)	⬆️
intelmq/bots/outputs/smtp/output.py	79.36% <0.00%> (+0.67%)	⬆️

[ghost]

otherwise ready for merge (tests are appreciated but not required)

[monoidic]

Ah, right. I'll add some tests on monday (friday's a national holiday).

[monoidic]

I added validate=True to the decode step, as by default, the base64 module just silently ignores invalid characters, which is the opposite of the intended effect, and some tests.

[ghost]

Thanks! also cherry-picked for maintenance (coming 3.0.1 release)