fix: correct duplicate parking:left:capacity in osmSummableTags

[JaiswalShivang]

fixes #11819

Summary

Fixes a typo in [modules/osm/tags.js] where parking:left:capacity was duplicated instead of including parking:right:capacity.

Problem

The osmSummableTags Set incorrectly contained:

export var osmSummableTags = new Set([
    'step_count',
    'parking:both:capacity',
    'parking:left:capacity',
    'parking:left:capacity'  // <-- Duplicate!
]);
## Previously
<img width="635" height="227" alt="image" src="https://github.com/user-attachments/assets/17fb218a-6655-4c79-897f-1db0e73be406" />
## After Updation
<img width="576" height="220" alt="image" src="https://github.com/user-attachments/assets/d6a7eeac-c9bc-45e8-849b-39e9bb495b19" />

[tordans]

Please add a changelog entry similar to how it was done in the last PRs.

[JaiswalShivang]

@tordans I have added the details in changelog.md