[perf] mark extension points dynamic (#8507)

<img width="1474" height="160" alt="image"
src="https://github.com/user-attachments/assets/26d02d31-540c-41dc-ae63-4eb03acbdf31"
/>

Since we support the usage rules detailed in the [Dynamic Extension
Point
docs](https://plugins.jetbrains.com/docs/intellij/plugin-extension-points.html?from=PluginXmlDynamicPlugin#dynamic-extension-points),
marking this dynamic should allow hot reloading of the plugin.

---

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portions to this PR.

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- See our [contributor
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Author: pq

resources/META-INF/plugin.xml

@@ -260,8 +260,8 @@
   </actions>
 
   <extensionPoints>
-    <extensionPoint name="gradleSyncProvider" interface="io.flutter.android.GradleSyncProvider"/>
-    <extensionPoint name="colorPickerProvider" interface="io.flutter.editor.ColorPickerProvider"/>
+    <extensionPoint name="gradleSyncProvider" interface="io.flutter.android.GradleSyncProvider" dynamic="true"/>
+    <extensionPoint name="colorPickerProvider" interface="io.flutter.editor.ColorPickerProvider" dynamic="true"/>
   </extensionPoints>
 
   <extensions defaultExtensionNs="io.flutter">