fix(planning): corrects typo in svg

[AA-T4]

Description

Fixes a subject-verb agreement error in an SVG file in Stop Line documentation.

Notes for reviewers

@yhisaki Please review this pull request when you have time.

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[yhisaki]

Thank you. LGTM.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 28.77%. Comparing base (f211728) to head (0063ac3).
Report is 22 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9814      +/-   ##
==========================================
- Coverage   28.78%   28.77%   -0.01%     
==========================================
  Files        1456     1458       +2     
  Lines      109129   109164      +35     
  Branches    42519    42521       +2     
==========================================
+ Hits        31416    31417       +1     
- Misses      74636    74670      +34     
  Partials     3077     3077              

Flag	Coverage Δ		*Carryforward flag
differential	2.92% <ø> (?)
total	28.78% <ø> (ø)		Carriedforward from f211728

*This pull request uses carry forward flags. Click here to find out more.

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