[BUG]: Create other date out of range

[mbiesiad]

Describe the bug

At this moment user can create a contribution with date other than 1-24 Dec (described in the description).

(it is greyed out when selecting from the calendar).

To Reproduce

Go to: https://24pullrequests.com/dashboard

Fill the fields, and set by manual date "out of range", ie. 28th Dec. See that contribution has been taken into account.

Expected Behavior

Description says about range: 1-24 Dec. It could be protected from entering other values out of range.

Display the appropriate notification.

Screenshot/ Video

Screenshots attached:

Additional context

No response

[andrew]

On a related note, we should hide currently invalid dates from the homepage