minor symfony#2358 [Map][Google] Add documentation about ux_map.google_maps.default_map_id (Kocal)

This PR was merged into the 2.x branch.

Discussion
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[Map][Google] Add documentation about `ux_map.google_maps.default_map_id`

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Issues        | Fix #... <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License       | MIT

<!--
Replace this notice by a description of your feature/bugfix.
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 - Always add tests and ensure they pass.
 - For new features, provide some code snippets to help understand usage.
 - Features and deprecations must be submitted against branch main.
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I've just tilted that I've missed to document the new feature introduced in symfony#2350 for symfony#2306

Commits
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18d7b6b [Map][Google] Add documentation about ux_map.google_maps.default_map_id

Author: Kocal

src/Map/doc/index.rst

@@ -34,6 +34,12 @@ Configuration is done in your ``config/packages/ux_map.yaml`` file:
     # config/packages/ux_map.yaml
     ux_map:
         renderer: '%env(resolve:default::UX_MAP_DSN)%'
+        
+        # Google Maps specific configuration
+        google_maps:
+            # Configure the default Map Id (https://developers.google.com/maps/documentation/get-map-id),
+            # without to manually configure it in each map instance (through "new GoogleOptions(mapId: 'your_map_id')").
+            default_map_id: null
 
 The ``UX_MAP_DSN`` environment variable configure which renderer to use.
 

src/Map/src/Bridge/Google/README.md

@@ -46,9 +46,12 @@ $map = (new Map())
     ->center(new Point(48.8566, 2.3522))
     ->zoom(6);
 
-// To configure controls options, and some other options:
+// To configure control options and other map options:
 $googleOptions = (new GoogleOptions())
-    ->mapId('YOUR_MAP_ID')
+    // You can skip this option if you configure "ux_map.google_maps.default_map_id"
+    // in your "config/packages/ux_map.yaml".
+    ->mapId('YOUR_MAP_ID') 
+    
     ->gestureHandling(GestureHandling::GREEDY)
     ->backgroundColor('#f00')
     ->doubleClickZoom(true)