docs: add destructuring actions with props example for createReducer

Closes #1985

projects/ngrx.io/content/guide/store/reducers.md

@@ -25,6 +25,7 @@ import { createAction } from '@ngrx/store';
 export const homeScore = createAction('[Scoreboard Page] Home Score');
 export const awayScore = createAction('[Scoreboard Page] Away Score');
 export const resetScore = createAction('[Scoreboard Page] Score Reset');
+export const setScores = createAction('[Scoreboard Page] Set Scores');
 
 </code-example>
 
@@ -72,7 +73,8 @@ const scoreboardReducer = createReducer(
   initialState,
   on(ScoreboardPageActions.homeScore, state => ({ ...state, home: state.home + 1 })),
   on(ScoreboardPageActions.awayScore, state => ({ ...state, away: state.away + 1 })),
-  on(ScoreboardPageActions.resetScore, state => ({ home: 0, away: 0 }))
+  on(ScoreboardPageActions.resetScore, state => ({ home: 0, away: 0 })),
+  on(ScoreboardPageActions.setScores, (state, { game }) => ({ home: game.home, away: game.away }))
 );
 
 export function reducer(state: State | undefined, action: Action) {
@@ -86,7 +88,8 @@ export function reducer(state: State | undefined, action: Action) {
 
 </div>
 
-In the example above, the reducer is handling 3 actions: `[Scoreboard Page] Home Score`, `[Scoreboard Page] Away Score`, and `[Scoreboard Page] Score Reset`. Each action is strongly-typed. Each action handles the state transition immutably. This means that the state transitions are not modifying the original state, but are returning a new state object using the spread operator. The spread syntax copies the properties from the current state into the object, creating a new reference. This ensures that a new state is produced with each change, preserving the purity of the change. This also promotes referential integrity, guaranteeing that the old reference was discarded when a state change occurred.
+In the example above, the reducer is handling 4 actions: `[Scoreboard Page] Home Score`, `[Scoreboard Page] Away Score`, `[Scoreboard Page] Score Reset` and `[Scoreboard Page] Set Scores`. Each action is strongly-typed. Each action handles the state transition immutably. This means that the state transitions are not modifying the original state, but are returning a new state object using the spread operator. The spread syntax copies the properties from the current state into the object, creating a new reference. This ensures that a new state is produced with each change, preserving the purity of the change. This also promotes referential integrity, guaranteeing that the old reference was discarded when a state change occurred.
+
 
 <div class="alert is-important">