[typescript-migration] some tests

[yuki0410-dev]

Description

Linked issue: #4700

Changes

• migrate src/test/month_test.test.tsx
• migrate src/test/week_number_test.test.tsx
• migrate src/test/multi_month_test.test.tsx
• migrate src/test/min_time_test.test.tsx
• migrate src/test/multiple_selected_dates.test.tsx

Contribution checklist

• [x] I have followed the contributing guidelines.
• [x] I have added sufficient test coverage for my changes.
• [x] I have formatted my code with Prettier and checked for linting issues with ESLint for code readability.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.

Project coverage is 96.94%. Comparing base (7231710) to head (3054d56).

Files	Patch %	Lines
src/index.tsx	66.66%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #4881 +/- ## ========================================== - Coverage 96.96% 96.94% -0.03% ========================================== Files 28 28 Lines 3234 3242 +8 Branches 1341 1332 -9 ========================================== + Hits 3136 3143 +7 - Misses 94 99 +5 + Partials 4 0 -4 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.