rectangles: Add new large test
rectangles: Add new large test

This was added to x-common in
https://github.com/exercism/x-common/pull/288

It originated from the Lua track. Neither this track nor the Python
track had it prior.

sacherjj/rust,exercism/xrust,petertseng/exercism-rust,exercism/xrust,sacherjj/rust,petertseng/exercism-rust,petertseng/exercism-rust,sacherjj/rust