/api/sendMail only sends with `defaultFrom`

[maxaggedon]

Describe the bug
from option is correctly shown in intercept but not used

To Reproduce
Steps to reproduce the behavior:

1. Use /api/sendMail endpoint with a from
2. Force send if in preview mode
3. Actual email has the defaultFrom value as From header

Expected behavior
If specified, from field should be used

Desktop (please complete the following information):

• OS: macOS
• Browser: Chrome
• Version: 1.0.1