Update exists (pre-PR) tests to pass

One test relied upon constraints NOT being applied transitively. The
other was named incorrectly, it was testing a non-root scenario but was
named "transitive" which was misleading.

gps/solve_bimodal_test.go

@@ -188,12 +188,12 @@ var bimodalFixtures = map[string]bimodalFixture{
 		},
 		r: mksolution(
 			"a 1.0.0",
-			"b 1.1.0",
+			"b 1.0.0", // Now that constraints can be applied transitively, the constraint from root applies
 		),
 	},
 	// Constraints apply only if the project that declares them has a
 	// reachable import - non-root
-	"constraints activated by import, transitive": {
+	"constraints activated by import, non-root": {
 		ds: []depspec{
 			dsp(mkDepspec("root 0.0.0"),
 				pkg("root", "root/foo", "b"),