Make the tag edit box on the body admin page bigger.

[HelenWDTK]

When a body has a lot of tags, it is hard to scroll through these to edit them, as the text field is quite small.

https://github.com/mysociety/alaveteli/assets/120410992/76f5105e-1b9c-4442-868c-0cbf203084d4

It would be good to make this box bigger, or to display the tags in some other way which makes them easier to remove