prune release 0.18 items from release_dev.rst

[grlee77]

Description

It seems that items from release 0.18 are still in release_dev.rst. This came up in #4946 (comment) where the documentation section was pruned. We should check over the remainder of the file to avoid having duplicate entries from the prior release.

[hmaarrfk]

We should really move to towncrier. It has been a dream of mine to suggest the infrastructure changes but I never had time to complete it. It really makes release notes painless.

[grlee77]

Yes, towncrier is one of the items we discussed recently for CI work funded under the CZI grant. I think @leej3 and @viniciusdc will be taking a look at this in the relatively near future.

[leej3]

Yes. If all goes well I would say in 2-4weeks. My confidence interval shall shrink rapidly at the end of the week.