delete minor unreachable code caused by log.Fatal

[Abirdcfly]

Signed-off-by: Abirdcfly fp544037857@gmail.com

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[codecov]

Codecov Report

Merging #1831 (a15e579) into master (3a25147) will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1831      +/-   ##
==========================================
- Coverage   36.28%   36.26%   -0.02%     
==========================================
  Files         232      232              
  Lines       19496    19496              
==========================================
- Hits         7074     7071       -3     
- Misses      11592    11594       +2     
- Partials      830      831       +1     

Flag	Coverage Δ
unit	36.26% <ø> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
arduino/cores/packagemanager/package_manager.go	62.18% <0.00%> (-0.85%)	⬇️

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