Bug description

Nyquist plugins create an unwanted clip when applied at the end of a clip.

upon further testing, it seems that only Studio Fade Out is affected.

Testing shows that this is a regression on 3.3.3

Steps to reproduce

The issue is not 100% reproducible and most likely depends on the selection length

1. Generate a 30 second tone
2. Select for 10 secs
3. apply Studio Fade Out
4. Observe a clip boundary is crated at 20 seconds
5. If a new clip is not created try again starting with the step 2

Expected behavior

No clip break created when using the effect

Actual behavior

Unwanted clip beak created when using the effect

Audacity Version

Audacity 3.7.4-alpha

Operating system

OS independent

Additional context

Originally reported #8468