docs: update bech32 account docs

[robert-zaremba]

Description

closes: #8053

---

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[amaury1093]

Thanks! I did a ctrl+F on the whole codebase, found these occurrences:

• docs/core/node.md:L20: "addresses and pubkeys"
• docs/spec/addresses/bech32.md: still some pubkeys

[amaury1093]

lgtm

[orijbot]

Benchmark beginning. Status page: https://github.orijtech.com/benchmark/status?commit=35af39ed3def9851d413c00366f3aebc2199d431