Update a few dependencies

[regexident]

This PR applies the following dependency updates:

• itertools from "0.12" to "0.13"
• rustc-hash from "1.1" to "2.0"
• duplicate from "1.0" to "2.0"

---

With this the following outdated dependencies remain:

$ cargo outdated -R

ascent-byods-rels
================
Name         Project  Compat  Latest  Kind    Platform
----         -------  ------  ------  ----    --------
derive_more  0.99.18  ---     1.0.0   Normal  ---
hashbrown    0.14.5   ---     0.15.0  Normal  ---
syn          1.0.109  ---     2.0.85  Normal  ---

ascent
================
Name       Project  Compat  Latest  Kind    Platform
----       -------  ------  ------  ----    --------
boxcar     0.1.0    ---     0.2.6   Normal  ---
dashmap    5.5.3    ---     6.1.0   Normal  ---
hashbrown  0.14.5   ---     0.15.0  Normal  ---

… which would require significantly more time to update due to breakages.