holdShelfExpirationDate should honour closed days configured in Exception period in Calendar settings

Steps to reproduce

1. Go to Calendar, click Add a new exception period

2. Create an exception period which states that the library is closed 2020-03-18 through 2020-03-31

3. Save the new Exception period

4. On 2020-03-18, check in an item which has a request

Expected result

The standard hold expiration period is 7 days, but since that date falls within the exception period, holdShelfExpirationDate is set to 7 days from now excluding the days closed according to the Exception period (during which the patron will have no possibility of picking up the book). The holdShelfExpirationDate should be something like 2020-04-07.

Actual result

The holdShelfExpirationDate is set to 2020-03-25, i.e. 7 days from now, even though this means the patron will have no chance to pick up the book.