fix: force WebDriver creation if DriverSupplier returns null (#1787) (#…

…1788)

Co-authored-by: Marco Collovati <marco@vaadin.com>

vaadin-testbench-core-junit5/src/main/java/com/vaadin/testbench/browser/BrowserExtension.java

@@ -215,13 +215,16 @@ private WebDriver createDriver(ExtensionContext context,
 
         Object testInstance = context.getRequiredTestInstance();
 
+        WebDriver webDriver;
+
         // use WebDriver provided by test instance
         if (testInstance instanceof DriverSupplier supplier) {
-            return supplier.createDriver();
+            webDriver = supplier.createDriver();
+            if (webDriver != null) {
+                return webDriver;
+            }
         }
 
-        WebDriver webDriver;
-
         Class<?> testClass = context.getRequiredTestClass();
         // Always give priority to @RunLocally annotation
         if ((getRunLocallyBrowser(testClass) != null)) {