Bump exchange-calendars from 4.12 to 4.13 (#212)

Bumps [exchange-calendars](https://github.com/gerrymanoim/exchange_calendars) from 4.12 to 4.13.
- [Release notes](https://github.com/gerrymanoim/exchange_calendars/releases)
- [Changelog](https://github.com/gerrymanoim/exchange_calendars/blob/master/docs/changes_archive.md)
- [Commits](gerrymanoim/exchange_calendars@4.12...4.13)

---
updated-dependencies:
- dependency-name: exchange-calendars
  dependency-version: '4.13'
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -4,5 +4,5 @@ pydantic==2.12.5
 uvicorn==0.40.0
 slowapi==0.1.9
 email-validator==2.3.0
-exchange_calendars==4.12
+exchange_calendars==4.13
 holidays==0.88