Fix SAPI4 WASAPI implementation (#17999)
Fixes #17964
Summary of the issue:
Responsiveness issue when using the SAPI4 version of Infovox desktop standard voices.
Seems that commit c26c1c9 caused the issue.
Description of user facing changes
The issue mentioned above should be fixed.
Description of development approach
Removed the 2-second size limit on the buffer. FreeSpace still returns a "2 seconds" size, but the size is actually unlimited, and audio data will never be rejected because of insufficient buffer size.
