Update esp-wifi to match changes made to esp-hal

[MikeGstefan]

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Submission Checklist 📝

• I have updated existing examples or added new ones (if applicable).
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• My changes were added to the CHANGELOG.md in the proper section.
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Pull Request Details 📖

Description

Changes to allow the development of projects using both esp-hal and esp-wifi

Bump version of embassy-sync to 0.6.1 to match the change to esp-hal made in (#2555) which prevented compilation of projects with both dependencies

Enabled the unstable feature on the esp-hal dependency introduced in (#2628) which is required for esp-wifi to compile

Testing

Projects which depend on upstream esp-hal can now compile

[bugadani]

Thank you but we don't want to enable the unstable feature automatically. Doing so would mean that some users would be able to use unstable APIs without opting into them explicitly - and so they may not know the limitations and lack of guarantees on them.

We might want to look into stabilizing what esp-wifi needs in the near term, but for now the solution should be documenting that esp-wifi requires esp-hal/unstable.