rust/filecontainer: fix double implementation

[linuxhunter]

Default was implemented twice on the FileContainer struct

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Describe changes:

#suricata-verify-pr: #suricata-verify-repo: #suricata-verify-branch: #suricata-update-pr: #suricata-update-repo: #suricata-update-branch: #libhtp-pr: #libhtp-repo: #libhtp-branch:

[codecov[bot]]

Codecov Report

Merging #7722 (6369421) into master (9b4a133) will decrease coverage by 0.02%. The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #7722      +/-   ##
==========================================
- Coverage   75.99%   75.96%   -0.03%     
==========================================
  Files         660      660              
  Lines      185718   185717       -1     
==========================================
- Hits       141131   141077      -54     
- Misses      44587    44640      +53     

Flag	Coverage Δ
fuzzcorpus	60.74% <ø> (+0.03%)	:arrow_up:
suricata-verify	52.55% <ø> (-0.01%)	:arrow_down:
unittests	60.70% <ø> (-0.01%)	:arrow_down:

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