Fix modules without return type throwing segmentation fault

tests/integration/ModuleTests.cpp

@@ -24,7 +24,14 @@ local module = {
 }
 return module
 )")
-                }
+                },
+                {"simple_no_return", Script::Create(u"foo = 500")},
+                {"no_return_with_local", Script::Create(uR"(
+local foo = 684
+function bar()
+    return foo
+end
+)")},
             };
         }
 
@@ -106,5 +113,31 @@ return list.contains({"foo", "bar"}, "bar")
     delete script;
 }
 
+TEST_CASE( "Simple no return module", "[integration]" ) {
+    ModuleHandler::Initialize();
+    auto script = Script::Create(uR"(
+require("simple_no_return")
+return foo
+)");
+    REQUIRE(!script->Diagnostics -> HasErrors());
+    auto result = script->Evaluate();
+    CHECK(result->EvaluateInteger() == 500);
+
+    delete script;
+}
+
+TEST_CASE( "Simple no return module with local variable", "[integration]" ) {
+    ModuleHandler::Initialize();
+    auto script = Script::Create(uR"(
+require("no_return_with_local")
+return bar()
+)");
+    REQUIRE(!script->Diagnostics -> HasErrors());
+    auto result = script->Evaluate();
+    CHECK(result->EvaluateInteger() == 684);
+
+    delete script;
+}
+
 
 #endif