[Performance]: `resolve_modifier_with_entrypoints` tracks visited node in a `Vec`, using a `HashSet` should be better

[nicolaassolini-qntm]

Performance Issue

We are using a vector for visited nodes in two places:

tket2/tket/src/modifier/modifier_resolver.rs

Line 1084 in 1f7df21

let mut visited = vec![];

tket2/tket/src/modifier/modifier_resolver.rs

Line 1113 in 1f7df21

let mut visited = vec![];