Documentation: quizBankID should be a number

[swashbuck]

Subject of the enhancement

According to the schemas, _quizBankID should be a number. We should update the documentation so that this is reflected. In the readme, the number is shown as a string with quotes.

adapt-contrib-assessment/README.md

Line 85 in 5179537

>>**\_split** (string): This is a comma-separated list of numbers corresponding to the number of questions to be drawn from each identified block. The *position* of the numeral in the list corresponds to the **\_quizBankID** assigned to a block. The *value* of the number determines how many questions to retrieve randomly from that particular quiz bank. For example, a **\_split** with a value of "2,1" would pick 2 questions from bank 1 (`"_quizBankID": "1"`) and 1 question from bank 2 (`"_quizBankID": "2"`).

_split (string): This is a comma-separated list of numbers corresponding to the number of questions to be drawn from each identified block. The position of the numeral in the list corresponds to the _quizBankID assigned to a block. The value of the number determines how many questions to retrieve randomly from that particular quiz bank. For example, a _split with a value of "2,1" would pick 2 questions from bank 1 ("_quizBankID": "1") and 1 question from bank 2 ("_quizBankID": "2").