Add Pass.NoCopy unit test

test/util/pass.test.cpp

@@ -0,0 +1,16 @@
+#include <mbgl/test/util.hpp>
+
+#include <mbgl/util/pass_types.hpp>
+
+TEST(Pass, NoCopy) {
+    static int copyCount = 0;
+    struct A {
+        A() = default;
+        A(A&&) = default;
+        A(const A&) { ++copyCount; }
+        static mbgl::Pass<A> create() { return A(); }
+    };
+    A a = A::create();
+    (void)a;
+    EXPECT_EQ(0, copyCount);
+}