fix: Relax model validation constraints for Plan and StoreListActor

[apify-service-account]

Important

Replace this PR title and description before merging.

• Title: a Conventional Commits message describing the actual model changes (e.g. chore: ... for a routine sync, or refactor:/feat:/fix: when models meaningfully change).
• Description: summarize what changed in the models.

• Updates the auto-generated Pydantic models and TypedDicts based on the proposed OpenAPI specification changes.
• Based on apify-docs PR #2707.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.54%. Comparing base (e1f3217) to head (8fe428c).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #910      +/-   ##
==========================================
+ Coverage   94.52%   94.54%   +0.01%     
==========================================
  Files          48       48              
  Lines        5098     5098              
==========================================
+ Hits         4819     4820       +1     
+ Misses        279      278       -1     

Flag	Coverage Δ
integration	92.91% <100.00%> (+0.27%)	⬆️
unit	83.36% <100.00%> (ø)

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[vdusek]

LGTM