Return HTTP status 400 if missing JWT

[kitloong]

Fixes

echo-jwt/jwt.go

Lines 159 to 161 in 6944ffe

	// For valid token, it sets the user in context and calls next handler.
	// For invalid token, it returns "401 - Unauthorized" error.
	// For missing token, it returns "400 - Bad Request" error.

https://echo.labstack.com/docs/middleware/jwt

Should return HTTP status 400 if missing JWT as documented.

[kitloong]

Hi @aldas

I am sorry, just a kind reminder to review in case you have missed this, thank you!

[aldas]

LGTM