docs(linter): Fix the rule config docs for eslint/no-inner-declarations rule.

[connorshea]

This fixes the no-inner-declarations docs by treating them as a tuple. Although, it also breaks the tests for no-inner-declarations. 🙃

I think there may be a bug in the tests/logic for our no-inner-declarations rule (I think oxc assumes strict mode by default maybe?). We previously returned None for block_scoped_expressions instead of allow, which the original rule does not do. It always just sets allow as the default value as far as I can tell.

I'm unsure if I should add an impl Default for NoInnerDeclarationsConfigObject and set it to return None, and retain that behavior, or if we should fix this behavior to match the original ESLint rule better? Up to cam, probably.

Generated docs:

## Configuration

### The 1st option

type: `"functions" | "both"`

#### `"functions"`

Disallows function declarations in nested blocks.

#### `"both"`

Disallows function and var declarations in nested blocks.

### The 2nd option

This option is an object with the following properties:

#### blockScopedFunctions

type: `"allow" | "disallow"`

##### `"allow"`

Allow function declarations in nested blocks in strict mode (ES6+ behavior).

##### `"disallow"`

Disallow function declarations in nested blocks regardless of strict mode.

[codspeed-hq]

CodSpeed Performance Report

Merging #16556 will not alter performance

_{Comparing inner-decls (6f5894b) with handle-tuple-rules-better (3abce5e)}

Summary

✅ 4 untouched
⏩ 41 skipped¹

Footnotes

1. 41 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[connorshea]

Marking as a draft until we have a discussion on whether this current behavior is the desired one.

[xuanduc987]

I believe we can use serde_json::from_value::<SortKeys>(value) here, so the change to DefaultRuleConfig is unnecessary?