remove redundant code mentioning ToCsv (#7370)

# Description

```rust
ToCsv
```

ToCsv was in there twice so I removed the 2nd reference...

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guide](../CONTRIBUTING.md) and talk to the core team before making major
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# User-Facing Changes

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# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
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# After Submitting

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PR is merged, if necessary. This will help us keep the docs up to date.

crates/nu-command/src/default_context.rs

@@ -343,7 +343,6 @@ pub fn create_default_context() -> EngineState {
             ToText,
             ToToml,
             ToTsv,
-            ToCsv,
             Touch,
             Use,
             Upsert,