Fix Word legacy spelling errors reporting (#19972)
Fix-up of #17997
[Reported](https://groups.io/g/nvda-fr/topic/nvda_2026_1_beta_et_l_annonce/118894622)
on French mailing list.
### Summary of the issue:
In 2026.1beta versions, spelling errors are no longer reported in Word
legacy.
### Description of user facing changes:
Spelling errors can now again be reported in Word legacy.
### Description of developer facing changes:
N/A
### Description of development approach:
In #17997, the config key "reportSpellingErrors" has been modified to
"reportSpellingErrors2" due to upgrade. But one use of this config key
has been forgotten. It is being fixed here.
### Testing strategy:
Manual tests with legacy and UIA Word.
### Known issues with pull request:
N/A
