Cherry-picking PR #6509
By pre-creating the hasher, instead of creating new one everytime addrbook.hash is called.
```
name old time/op new time/op delta
AddrBook_hash-8 181ns ±13% 80ns ± 1% -56.08% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
AddrBook_hash-8 216B ± 0% 8B ± 0% -96.30% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
AddrBook_hash-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
```
Fixed#6508
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#### PR checklist
- [x] Tests written/updated, or no tests needed
- [x] `CHANGELOG_PENDING.md` updated, or no changelog entry needed
- [x] Updated relevant documentation (`docs/`) and code comments, or no
documentation updates needed
