Improve Sanitization of Canvas Assignment Names

[timkato]

From @andrew-gardener
its using the same sanitizer as course name https://github.com/ubc/webwork2/blob/ubc/lib/WebworkBridge/Bridges/LTIBridge.pm#L69 & https://github.com/ubc/webwork2/blob/ubc/lib/WebworkBridge/Bridges/LTIBridge.pm#L76
course names don't allow periods because its used in for database tables names
a new sanitizer could be made for the assignment names (though it would cause problems for existing lti links so couldn't be done during the term)
UBC ENHC0011934

[kitsook]

Using the course name sanitizer also limits the quiz / assignment name to be 40 char in length (again, because of mysql limitation. Course name is used as table name). ref INC1780885