`suffixifyByHash` doesn't properly suffixify an indirect dependency name

[mitchellwrosen]

Input:

```ucm
scratch/main> builtins.merge lib.builtin

lib.direct.foo = 17
lib.direct.lib.indirect.foo = 18

thing = indirect.foo + indirect.foo

scratch/main> add
scratch/main> view thing

Output:

thing : Nat thing = use Nat + foo + foo