Use OneIndexed in NotebookIndex (#7921)

## Summary

This PR refactors the `NotebookIndex` struct to use `OneIndexed` to make
the
intent of the code clearer.

## Test Plan

Update the existing test case and run `cargo test` to verify the change.

- [x] Verify `--diff` output
- [x] Verify the diagnostics output
- [x] Verify `--show-source` output

crates/ruff_linter/src/logging.rs

@@ -177,18 +177,15 @@ impl Display for DisplayParseError<'_> {
                     f,
                     "cell {cell}{colon}",
                     cell = jupyter_index
-                        .cell(source_location.row.get())
-                        .unwrap_or_default(),
+                        .cell(source_location.row)
+                        .unwrap_or(OneIndexed::MIN),
                     colon = ":".cyan(),
                 )?;
 
                 SourceLocation {
-                    row: OneIndexed::new(
-                        jupyter_index
-                            .cell_row(source_location.row.get())
-                            .unwrap_or(1) as usize,
-                    )
-                    .unwrap(),
+                    row: jupyter_index
+                        .cell_row(source_location.row)
+                        .unwrap_or(OneIndexed::MIN),
                     column: source_location.column,
                 }
             } else {