Improve kind verbosity logic

[liam923]

This PR addresses a minor bug in the kind hover implementation. Before this PR, as verbosity increases, Merlin would sometimes show the same kind twice. For example, when printing value mod portable, it gives:

Verbosity 0: value mod portable
Verbosity 1: value mod portable
Verbosity 2: value mod portable internal non_null separable

This creates an issue for the LSP, which only displays an option to the user to increase verbosity if the next verbosity level is different from the current level. In the case of value mod portable, this means there's no way to expand the kind beyond value mod portable. This PR fixes that.

[dkalinichenko-js]

This feels hacky, but I guess we just have to do what the LSP wants in this case.