docs: fix typos

[monkeynioabs]

Summary

• [n] | Does it introduce breaking changes?
• [n] | Is it dependent on a specific version of cargo-contract or pallet-revive?
  Fix various typos in comments and error messages across the codebase

Description

This PR fixes several typos in comments and error messages:

1. In comments: Changed "map accout" to "map_account"
2. In comments: Corrected "everbody" to "everybody"
3. In error message: Fixed "instatiating" to "instantiating"

These changes improve readability and code quality without affecting any functionality.

Checklist before requesting a review

• I have added an entry to CHANGELOG.md
• I have commented on my code, particularly in hard-to-understand areas
• I have added tests that prove my fix is effective or that my feature works
• Any dependent changes have been merged and published in downstream modules

[Daanvdplas]

Thank you!