Documentation changes related to context code snippets

[imbus64]

The way the documentation demonstrates context usage does not work for me (panics on expect).
Its unclear if this is because im running a BrowserRouter in between the context provider and consumers. Either way, adding the Rc makes it work as expected.

This change just concerns the 0.20 version of the docs.

[github-actions]

Visit the preview URL for this PR (updated for commit c2fb476):

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[cecton]

Actually not sure if this is a bug that should be addressed later on or not.

@hamza1311 what do you think?

In any case, the code in the documentation should be working and if this works we should merge this right now (otherwise it's terrible for the users). We can add a comment somewhere or open an issue to fix this one later (if this is actually a bug).

[ranile]

Actually not sure if this is a bug that should be addressed later on or not.

This was a bug... in the code snippet. The types need to be same. It Rc'd later on but not at call site