Enable testing localhost urls on development server

[whatisgalen]

…s.DEBUG, re #10932

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Description of Change

if DEBUG is true, the url datatype will let you save urls that include "localhost" (useful if a url is pointing to somewhere else in the arches instance)

Issues Solved

#10932

Checklist

• Unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Ticket Background

• Sponsored by: @scholiumtech
• Found by: @whatisgalen
• Tested by: @
• Designed by: @whatisgalen

Further comments