Highlight "size" as a keyword in array literal context

[tcNickolas]

Is your feature request related to a problem? Please describe.
Q# Jupyter Notebooks don't highlight "size" as a keyword.

Describe the solution you'd like
Highlight "size" as a keyword in the context of array literals: something like "a comma, optional whitespace, size, optional whitespace, equality sign" should highlight "size" as a keyword, but other contexts shouldn't.

let size = 123;
let xs = [size, size = 2]; // first size is a variable, second size is a "keyword"