extract isPlaybackActive to a global util function (#1393)

packages/utils/src/playback-utils/playbackstate.ts

@@ -0,0 +1,10 @@
+import { Playback } from 'ontime-types';
+
+/**
+ * Utility checks whether the playback is considered to be active
+ * @param state
+ * @returns
+ */
+export function isPlaybackActive(state: Playback): boolean {
+  return state === Playback.Play || state === Playback.Pause || state === Playback.Roll;
+}