docs: fix sender email object description in MailHelper.cs

[makma]

Fixes

I believe there are mistakes in the documentation for creating emails in MailHelper.cs.
I reckon that the from object should represent the sender, thus there should be the sender's name instead of the recipient's name.

Checklist

• I acknowledge that all my contributions will be made under the project's license
• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the Contribution Guidelines and my PR follows them
• I have titled the PR appropriately
• I have updated my branch with the main branch
• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary documentation about the functionality in the appropriate .md file
• I have added inline documentation to the code I modified

[childish-sambino]

Nice catch!