Change maximum attachment size in email

Hello guys,
I need to change the attached file limit, it presents an error when I try to place a file larger than 1mb, can anyone tell me where I can change this configuration?

Current Version: 2.3
Build: 2

Current Commit: 60d048f82acbf3a35b626f0f33782c4c73e77b86
Latest Version: 2.3

Latest Build: 4
Latest Commit: 63cd467b5a7882ad2b4a207ce748e8446838c376