smtpapi_test: dont ignore error in test

[keydrevolta]

Checklist

• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the [Contribution Guide] and my PR follows them.
• I updated my branch with the master branch.
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation about the functionality in the appropriate .md file
• I have added in line documentation to the code I modified

Short description of what this PR does:

• Updates a test so It won't ignore a possible error from a function

[SendGridDX]

All committers have signed the CLA.

[thinkingserious]

Hello @keydrevolta,

Thanks again for the PR!

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[keydrevolta]

thanks @thinkingserious, i've just submitted the form.