Increase coverage

extras/tests/JsonVariant/unbound.cpp

@@ -44,6 +44,7 @@ TEST_CASE("Unbound JsonVariant") {
     CHECK_FALSE(variant.set(42L));
     CHECK_FALSE(variant.set(42U));
     CHECK_FALSE(variant.set(serialized("42")));
+    CHECK_FALSE(variant.set(serialized(std::string("42"))));
     CHECK_FALSE(variant.set(true));
   }
 
@@ -63,4 +64,13 @@ TEST_CASE("Unbound JsonVariant") {
     CHECK_FALSE(variant["key"].set(1));
     CHECK_FALSE(variant[std::string("key")].set(1));
   }
+
+  SECTION("containsKey()") {
+    CHECK_FALSE(variant.containsKey("hello"));
+  }
+
+  SECTION("remove()") {
+    variant.remove(0);
+    variant.remove("hello");
+  }
 }