Output notx 6846 v7

[catenacyber]

Link to redmine ticket:
https://redmine.openinfosecfoundation.org/issues/6846

Describe changes:

• output/alert: do not use tx_id 0 when there is no transaction

#10655 rebased to get attention

[codecov]

Codecov Report

Attention: Patch coverage is 89.47368% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 82.93%. Comparing base (240e068) to head (969491a).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10876      +/-   ##
==========================================
- Coverage   82.95%   82.93%   -0.02%     
==========================================
  Files         917      917              
  Lines      247367   247379      +12     
==========================================
- Hits       205198   205173      -25     
- Misses      42169    42206      +37     

Flag	Coverage Δ
fuzzcorpus	64.48% <89.47%> (-0.03%)	⬇️
suricata-verify	62.29% <89.47%> (-0.03%)	⬇️
unittests	62.29% <36.84%> (-0.01%)	⬇️

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[victorjulien]

Merged in #10887, thanks!