Hot topics on testing and cloud

[Pey Lian Lim]

Several inter-related topics are being actively discussed. Community inputs would help drive the decisions one way or another. Please comment on the issues if you are interested. Thanks!

* Do not include tests in Astropy wheels (reduce wheel size for AWS Lambda) -- https://github.com/astropy/astropy/issues/16152

* Deprecate astropy test runner (core and downstream) -- https://github.com/astropy/astropy/issues/16177

* Move astropy to src directory (probably the most controversial but re-opened because this would make not including tests in wheels easier to pull off) -- https://github.com/astropy/astropy/issues/13678