Improve error handling if logging in fails

[lil5]

Errors shown to the client if logging-in fails needs to be improved, returning an error that is understandable.

Cases to test are including:

1. brevo api call returns status an error
   1. 500 Internal Server Error: Our email server is having some difficulties, please try again later
   2. Invalid email: This email address seems invalid or does not exist in our database
   3. Blocked email (If possible): You may have marked our email address as spam. Please send us an email to unblock you at [email protected]
2. Server is not live: The Clothing Loop website is not working, please try again later or send us an email at [email protected]

[paloeka]

My updates: brevo api call returns status an error:

• 500 Internal Server Error: Our email server is having some difficulties, please try again later
• Invalid email: This email address seems invalid or does not exist in our database
• Blocked email (If possible): You may have marked our email address as spam. Please send us an email to unblock you at [email protected]

Server is not live:

• The Clothing Loop website is not working, please try again later or send us an email at [email protected]

[paloeka]

https://github.com/the-clothing-loop/website/issues/758 this issue is part of this one