Fixed bug where + wouldn't expand or collapse the hidden <div> for Mirage2 Community List

In community-list when a DSpace has a handle prefix configured with a '.' in it (example handle prefix: 2346.1) the data-target value in the <a> tag for the + sign would not match the id in the <div>

Fixed it by replacing instances of '.' in a handle prefix with '_' to sanitize the handle being used in the <div> and <a> tags in community-list