test: Adds SchemaBuilder connection test

Author: NeedleInAJayStack

Tests/GraphitiTests/SchemaBuilderTests.swift

@@ -29,6 +29,8 @@ class SchemaBuilderTests: XCTestCase {
             }.description(
                 "A large mass, planet or planetoid in the Star Wars Universe, at the time of 0 ABY."
             )
+        }.add {
+            ConnectionType(Planet.self)
         }.add {
             Enum(Episode.self) {
                 Value(.newHope)
@@ -120,5 +122,11 @@ class SchemaBuilderTests: XCTestCase {
                 ],
             ])
         )
+        
+        XCTAssert(
+            api.schema.schema.typeMap.contains(where: { key, _ in
+                key == "PlanetConnection"
+            })
+        )
     }
 }