fix: support @import string

[neilime]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 97.43590% with 1 line in your changes missing coverage. Please review.

Project coverage is 95.94%. Comparing base (e3cd551) to head (a745cfb).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/CssLint/Linter.php	97.43%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #113      +/-   ##
============================================
+ Coverage     95.80%   95.94%   +0.14%     
- Complexity      170      177       +7     
============================================
  Files             4        4              
  Lines           429      444      +15     
============================================
+ Hits            411      426      +15     
  Misses           18       18              

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