Fixed a bug where a trailing slash in the target URL of a UMD app will break deployment.

I'd probably name these similarly since they are checking for the same end result given two different input variants.  

Not sure if you've seen this pattern before for the JS tests, but you can do this sort of thing too:

[ { target: target1, expected: expected1 },
  { target: target2, expected: expected2 } ].forEach( function( useCase ) {
      it( 'blah blah blah', function() {
            builder.build( useCase.target ).loader.should.have.property( 'endpoint', useCase.expected );
      } );
} );

But in this case it is perhaps not worth the added complexity since there's only the two cases.