Revert "Use correct range to highlight line continuation error"

[dhruvmanila]

This PR reverts #12016 with a small change where the error location points to the continuation character only. Earlier, it would also highlight the whitespace that came before it.

The motivation for this change is to avoid panic in #11950. For example:

\)

Playground: https://play.ruff.rs/87711071-1b54-45a3-b45a-81a336a1ea61

The range of Unknown token and Rpar is the same. Once #11950 is enabled, the indexer would panic. It won't panic in the stable version because we stop at the first Unknown token.

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

ℹ️ ecosystem check encountered linter errors. (no lint changes; 1 project error)

demisto/content (error)

ruff check --no-cache --exit-zero --ignore RUF9 --output-format concise --preview

warning: The top-level linter settings are deprecated in favour of their counterparts in the `lint` section. Please update the following options in `pyproject.toml`:
  - 'ignore' -> 'lint.ignore'
  - 'select' -> 'lint.select'
  - 'unfixable' -> 'lint.unfixable'
  - 'per-file-ignores' -> 'lint.per-file-ignores'
warning: `PGH001` has been remapped to `S307`.
warning: `PGH002` has been remapped to `G010`.
warning: `PLR1701` has been remapped to `SIM101`.
ruff failed
  Cause: Selection of deprecated rule `E999` is not allowed when preview is enabled.

Formatter (stable)

✅ ecosystem check detected no format changes.

Formatter (preview)

ℹ️ ecosystem check encountered format errors. (no format changes; 1 project error)

demisto/content (error)

ruff format --preview --exclude Packs/ThreatQ/Integrations/ThreatQ/ThreatQ.py

warning: The top-level linter settings are deprecated in favour of their counterparts in the `lint` section. Please update the following options in `pyproject.toml`:
  - 'ignore' -> 'lint.ignore'
  - 'select' -> 'lint.select'
  - 'unfixable' -> 'lint.unfixable'
  - 'per-file-ignores' -> 'lint.per-file-ignores'
warning: `PGH001` has been remapped to `S307`.
warning: `PGH002` has been remapped to `G010`.
warning: `PLR1701` has been remapped to `SIM101`.
ruff failed
  Cause: Selection of deprecated rule `E999` is not allowed when preview is enabled.