postgres password not recognized when entered in layer settings

[tpotter7]

Describe the bug
When I open a postgres layer and edit the connection field, if I put in a user and password, they are not found and I get an error saying that there is not password. If I put them into the mml file, then it works fine.

To Reproduce
Steps to reproduce the behavior:

1. Go to Layers
2. Create a postgres Layer
3. Fill out the other fields
4. Type something like this into the Connection field "dbname=osm host=x.y.com port=5432 user=postgresql password=something"
5. Get an error saying:
   Postgis Plugin: fe_sendauth: no password supplied
   Connection string: 'host=tilemilldev.cuveite2ttso.us-east-2.rds.amazonaws.com port=5432 dbname=osm connect_timeout=4'

Expected behavior
Entering user and password in the GUI works the same as entering them into the mml file with an editor.