Steps to reproduce:
1. Open the user's attached project "BootCorruptRepro.zip"
2. Navigate to Project settings-> Player-> Other and clear the Scripting Define Symbols area
3. Save and close the project
4. In the project root folder edit the "build.bat" file to point to the desired Unity version
5. Double click on the Build.bat (after some time an apk "app.apk" will appear)

Expected results: apk is not created and error is printed in log file
Actual results: apk "app.apk" is created in the project folder

Reproduction: 2018.4.31f1, 2019.4.24f1, 2020.2.3f5, 2021.1.2f1, 2021.2.0a16

Note:
- Scripting Define Symbol area is empty at first but becomes filled after every build
- The issue does not reproduce if building from the editor
- The issue does not reproduce with Standalone