Bump hashbrown@0.15.0 to 0.15.1 to fix vuln

[grtlr]

What

Fixes CI problems (https://github.com/rerun-io/rerun/actions/runs/12160549310/job/33913118372?pr=8313):

error[vulnerability]: Borsh serialization of HashMap is non-canonical
    ┌─ /home/runner/work/rerun/rerun/Cargo.lock:225:1
    │
225 │ hashbrown 0.15.0 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2024-0402
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2024-0402
    ├ The borsh serialization of the HashMap did not follow the borsh specification.
      It potentially produced non-canonical encodings dependent on insertion order.
      It also did not perform canonicty checks on decoding.
      
      This can result in consensus splits and cause equivalent objects to be
      considered distinct.
      
      This was patched in 0.15.1.

[github-actions]

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Result	Commit	Link
✅	0afae56	https://rerun.io/viewer/pr/8315

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