Fix bad content-length

[gpotter2]

• fixes HTTP Content_length field may not be an integer #4668

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.21%. Comparing base (7275516) to head (dcb89e6).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4676      +/-   ##
==========================================
- Coverage   81.90%   81.21%   -0.70%     
==========================================
  Files         359      359              
  Lines       86574    86619      +45     
==========================================
- Hits        70909    70344     -565     
- Misses      15665    16275     +610     

Files with missing lines	Coverage Δ
scapy/layers/http.py	82.16% <100.00%> (-0.56%)	⬇️

... and 24 files with indirect coverage changes