Prevent path traversal outside of project root.

[plannigan]

No description provided.

[codecov]

Codecov Report

Merging #307 (4454586) into main (49c7262) will increase coverage by 0.01%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #307      +/-   ##
==========================================
+ Coverage   99.22%   99.23%   +0.01%     
==========================================
  Files          31       31              
  Lines        1806     1834      +28     
  Branches      238      241       +3     
==========================================
+ Hits         1792     1820      +28     
  Misses         12       12              
  Partials        2        2              

Files Changed	Coverage Δ
.../_hyper_bump_it/cli/interactive/file_validation.py	100.00% <100.00%> (ø)
hyper_bump_it/_hyper_bump_it/error.py	98.89% <100.00%> (+0.06%)	⬆️
hyper_bump_it/_hyper_bump_it/files.py	100.00% <100.00%> (ø)