Number of days in a month

#[test]
fn test_april() {
    let start = std::time::Instant::now();
    let val = Solution::number_of_days(2023, 4);
    let expected = 30;
    log_result!(val == expected, "test_april", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_example1() {
    let start = std::time::Instant::now();
    let val = Solution::number_of_days(1992, 7);
    let expected = 31;
    log_result!(val == expected, "test_example1", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_example2() {
    let start = std::time::Instant::now();
    let val = Solution::number_of_days(2000, 2);
    let expected = 29;
    log_result!(val == expected, "test_example2", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_example3() {
    let start = std::time::Instant::now();
    let val = Solution::number_of_days(1900, 2);
    let expected = 28;
    log_result!(val == expected, "test_example3", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn test_leap_year() {
    let start = std::time::Instant::now();
    let val = Solution::number_of_days(2024, 2);
    let expected = 29;
    log_result!(val == expected, "test_leap_year", start, &expected, &val);
    assert_eq!(val, expected);
}