Fixed SwitchNavigatorConfig interface to use the correct backBehavior value for initialRoute. And added a test to cover this. (#25533)

types/react-navigation/index.d.ts

@@ -631,7 +631,7 @@ export interface SwitchNavigatorConfig {
   initialRouteName: string;
   resetOnBlur?: boolean;
   paths?: NavigationPathsConfig;
-  backBehavior?: 'none' | 'intialRoute';
+  backBehavior?: 'none' | 'initialRoute';
 }
 
 // Return createNavigationContainer

types/react-navigation/react-navigation-tests.tsx

@@ -288,6 +288,26 @@ function renderBasicSwitchNavigator(): JSX.Element {
     );
 }
 
+const switchNavigatorConfigWithInitialRoute: SwitchNavigatorConfig = {
+    initialRouteName: 'screen',
+    resetOnBlur: false,
+    backBehavior: 'initialRoute'
+};
+
+const SwitchNavigatorWithInitialRoute = SwitchNavigator(
+    routeConfigMap,
+    switchNavigatorConfigWithInitialRoute,
+);
+
+function renderSwitchNavigatorWithInitialRoute(): JSX.Element {
+    return (
+        <SwitchNavigatorWithInitialRoute
+            ref={(ref: any) => { }}
+            style={viewStyle}
+        />
+    );
+}
+
 /**
  * Drawer navigator.
  */