Element Call SPA integration (#1283)

* Integrate Element Call into EX, being able to open its URLs and handle the call in-app.
* Add custom scheme support with format `element:call?url=...`.
* Update androix.webkit
* Silence the foreground service notification.
- Allow foreground service tap action to re-open the ongoing call.
- Unify notification small icons in different modules using a vector one.

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Co-authored-by: ElementBot <benoitm+elementbot@element.io>

app/build.gradle.kts

@@ -198,6 +198,7 @@ dependencies {
     allLibrariesImpl()
     allServicesImpl()
     allFeaturesImpl(rootDir, logger)
+    implementation(projects.features.call)
     implementation(projects.anvilannotations)
     implementation(projects.appnav)
     anvil(projects.anvilcodegen)