[BigQuery] Support math operation together with array access

[tobiasheldring]

Describe the bug
Bigquery should support math operations together with array access eg. my_array[0] / 100. Now an error is received eg.

SyntaxError: Expected "#", "'", "(", ",", "--", ".", "/*", ";", "AS", "EXCEPT", "FOR", "FROM", "GROUP", "HAVING", "INTERSECT", "LIMIT", "ORDER", "QUALIFY", "SELECT", "UNION", "WHERE", "WINDOW", "WITH", "\"", "`", [ \t\n\r], [A-Za-z_], or end of input but "/" found.

Database Engine
BigQuery

To Reproduce
Add the following test case to BigQuery.spec,.js

   {
      title: 'math operation after array access',
      sql: ['SELECT my_array[0] / 100 FROM table1', 'SELECT my_array[0] / 100 FROM table1']
    }

I also tested this with Postgres parser where it seems to work fine