test(serializer): Add KeystrokeAction tests (#430)

* test: add basis of the unit testing of the uhk-common package

* test(serializer): Add KeystrokeAction tests

* fix(serializer): Fix KeystrokeAction scancode mapping

* test(serializer): Add NoneAction test cases

* test(serializer): Add MouseAction test cases

* test(serializer): Add PlayMacroAction test cases

* test(serializer): Add SwitchKeymapAction test cases

* test(serializer): Add UserConfiguration test cases

fix KeyAction mapping

* test(serializer): Add SwitchLayerAction test cases

packages/uhk-common/src/config-serializer/config-items/module.ts

@@ -57,6 +57,7 @@ export class Module {
                 if (keyAction && (macros || !(keyAction instanceof PlayMacroAction || keyAction instanceof SwitchKeymapAction))) {
                     return keyAction.toJsonObject(macros);
                 }
+                return null;
             })
         };
     }