feat(localDate): add dayOfWeek

[mrnagydavid]

In this PR, I have added the dayOfWeek function to the LocalDate.
This is because in AMG3, we sometimes need to know whether the date is on the weekend, and currently we need to use Date for this.

Because dayOfWeek is already implemented for LocalTime, I used the same implementation.

However, I have not implemented the setter, because:

• it was not a pain point in AMG3
• and I find it hard to reason about setting the day of week for an existing date. The user would need to remember or check the implementation to know if this moves the date forward or backward.

If we should add the setter for the sake of symmetry, let me know.

[kirillgroshkov]

Legit 👍