docs(versioning): auto-generate pin documentation

[jamietanna]

Changes

As a follow-up from #36261, we should auto-generate this in our
documentation to keep it up-to-date.

If the getPinnedValue function is present, we should imply
rangeStrategy=pin.

Context

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The public repository:

[jamietanna]

Currently:

• https://docs.renovatebot.com/modules/versioning/cargo/

Now:

# Cargo Versioning

## Identifier

 `cargo` 

## References

 - [https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html](https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html)

## Ranges/Constraints

✅ Ranges are supported.

Valid `rangeStrategy` values are: `bump`, `replace`, `pin`