ENH: input.py: More informative when asking for the password.

`input.py` now tells the user name and URL before asking for the password.

src/caosdb/connection/authentication/input.py

@@ -81,7 +81,10 @@ class InputCredentialsProvider(CredentialsProvider):
         else:
             self._username = input("Please enter the user name: ")
 
-        self._password = getpass.getpass("Please enter the password: ")
+        url = config["url"]
+        self._password = getpass.getpass(
+            "Please enter the password for `{}` at `{}`: ".format(
+                self._username, url))
 
     @property
     def password(self):