The query-string parser used by express
https://github.com/ljharb/qs#parsing-arrays
limits the size of arrays that are created from query strings to 20
items. Arrays larger than that are converted to objects using numeric
indices.
This commit fixes the coercion algorithm used by queries to
treat number-indexed objects as arrays. We still maintain a strict
understanding of an "array-like object" to limit the opportunity for
subtle bugs. In particular, the presence of non-index keys is an
indication that the object was not intended to be interpreted as
an array.