Improve test coverage

[codecov[bot]]

Codecov Report

Merging #17 (58bd4ea) into main (54e00ce) will increase coverage by 11.82%. The diff coverage is 86.73%.

@@             Coverage Diff             @@
##             main      #17       +/-   ##
===========================================
+ Coverage   42.33%   54.15%   +11.82%     
===========================================
  Files          22       22               
  Lines        1415     1673      +258     
===========================================
+ Hits          599      906      +307     
+ Misses        816      767       -49     

Files Changed	Coverage Δ
src/cache.rs	36.87% <0.00%> (+0.55%)	:arrow_up:
src/cmd/ignore.rs	0.00% <0.00%> (ø)
src/cmd/search.rs	0.00% <0.00%> (ø)
src/settings.rs	25.00% <0.00%> (+15.00%)	:arrow_up:
src/utils.rs	37.83% <40.62%> (-16.01%)	:arrow_down:
src/bookmarks/target_bookmarks.rs	66.30% <90.53%> (+56.99%)	:arrow_up:
src/bookmark_reader/chrome.rs	93.96% <100.00%> (ø)
src/bookmark_reader/firefox.rs	77.72% <100.00%> (ø)
src/bookmark_reader/simple.rs	100.00% <100.00%> (ø)
src/bookmarks/source_bookmarks.rs	90.47% <100.00%> (+62.56%)	:arrow_up:
... and 1 more

... and 1 file with indirect coverage changes