chore(data/finset/lattice): use more common name, fix spaces (#16336)
`coe_le_max_of_mem` -> `le_max`
`le_max_of_mem` -> `le_max_of_eq`
`min_le_coe_of_mem` -> `min_le`
`min_le_of_mem` -> `min_le_of_eq`
`coe_le_max_of_mem` is an analogue of `le_sup` and `min_le_coe_of_mem` is an analogue of `inf_le`, new names are more consistent with them.
Co-authored-by: Floris van Doorn <fpvdoorn@gmail.com>