fix(updater): fallback if tmp is on different mount point, closes #4500

[lucasfernog]

What kind of change does this PR introduce?

• Bugfix
• Feature
• Docs
• New Binding issue #___
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change?

• Yes, and the changes were approved in issue #___
• No

Checklist

• When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.
• I have added a convincing reason for adding this feature, if necessary

Other information

[lucasfernog]

I also removed the #[cfg(feature = "updater")]in the core.rs file since we do not have an specific feature for updater documentation generation anymore (we previously had one because the updater feature enabled the zip crate, which didn't cross compile for docs.rs - now fixed by removing its default features).

[Beanow]

I'll leave the call up to a maintainer, but my thoughts are addressed 👌

[lucasfernog]

Thanks for the review @Beanow