revert: nesso_n1: move expander and battery to external library

[facchinm]

We noticed that adding the expander code in the core has been a bad idea 🙃
Moving it out to https://github.com/arduino-libraries/Arduino_Nesso_N1 , while leaving here only an explicit error message (much more informative than just failing at link time).

@ubidefeo
@me-no-dev

[github-actions]

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Some issues found for the commit messages in this PR: the commit message "nesso_n1: move expander and battery to external library": type/action should be one of [change, ci, docs, feat, fix, refactor, remove, revert, test] Please fix these commit messages - here are some basic tips: follow Conventional Commits style correct format of commit message should be: <type/action>(<scope/component>): <summary>, for example fix(esp32): Fixed startup timeout issue allowed types are: change,ci,docs,feat,fix,refactor,remove,revert,test sufficiently descriptive message summary should be between 10 to 72 characters and start with upper case letter avoid Jira references in commit messages (unavailable/irrelevant for our customers) TIP: Install pre-commit hooks and run this check when committing (uses the Conventional Precommit Linter).

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