Fix Error Transporter[MailerService] is ready

[frezyn]

I just replaced debug with log in then, as that was what made the most sense. If the transporter is ok, it just returns a log ready message to the user.

Now the log appears like this:
[Nest] 18308 - 25/03/2024, 17:44:53 LOG [MailerService] Transporter is ready

[GFoniX]

I've already submitted a pull request to address this issue. Additionally, I've fixed some errors with Sendgrid, and I've made the transporter validation "Optional" in case it might disrupt other configurations.
#1133

[DonaldMurillo]

I've already submitted a pull request to address this issue. Additionally, I've fixed some errors with Sendgrid, and I've made the transporter validation "Optional" in case it might disrupt other configurations. #1133

I think this issue addresses only the nest logger message only

[frezyn]

cri cri