Add space after comma when exporting a name

[sergv]

I felt that since hls-explicit-imports-plugin puts spaces after commas then this code action should also do so for consistency.

[jneira]

This is a fix for a whitespace inconsistency similar to described in #2399, thanks fo the contribution!

[jneira]

lgtm, moreove looks better with a space imo

[michaelpj]

ghcide tests need updating

[sergv]

Thanks for catching the tests bit, I've fixed them.