Merge pull request #2315 from alphagov/3-becomes-4

Set min text message sender length to 4 characters

app/main/forms.py

@@ -644,7 +644,7 @@ class ServiceSmsSenderForm(StripWhitespaceForm):
         validators=[
             DataRequired(message="Can’t be empty"),
             Length(max=11, message="Enter 11 characters or fewer"),
-            Length(min=3, message="Enter 3 characters or more"),
+            Length(min=4, message="Enter 4 characters or more"),
             LettersNumbersAndFullStopsOnly(),
             DoesNotStartWithDoubleZero(),
         ]