Increase default page size to max

[nealrichardson]

The users API, for example, is paginated, and the max page size is 500, but connectapi has a default value of 20. The user payload is not very large, so returning 500 records at once shouldn't be a problem, and it would definitely be cheaper than making 25 HTTP requests to collect them all.

In posit-sdk-py, we went with making the max the default.