For anyone unaware, the domain 'example.com' is specifically reserved for the purpose of testing, so you don't have to worry about some rando reading emails sent to "test@gmail.com"

I don't get it. What does gmail.com have to do with example.com?

Is a public service announcement. If you’re using test@gmail.com to actually test something, you should probably be using test@example.com. Not everyone knows that example.com exists for these purposes.

That is of course unless you really intend to send an email to someone at test@gmail.com.