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Issue Description

When trying to send a mail with wrong server configuration, the adapter returns a success but when the transporter promise is rejected it falls back to parse which makes node crash by throwing an error.

Steps to reproduce

Use bad configuration in the transported or simply return a rejected promise in apiCallback

Actual Outcome

Crash report printed from node_modules/parse-server/lib/ParseServer.js#L261

Expected Outcome

The error should be handled or we should have the possibility to wait for a sucess/failure of the sending before returning to the client.

Failing Test Case / Pull Request

Environment

• API Mail Adapter version: 2.2.0
• Parse Server version: 5.4.0

Logs

express:router dispatching POST /requestPasswordReset
node_modules/parse-server/lib/ParseServer.js:261
          throw err;
          ^
Waiting for the debugger to disconnect...