[grid] Using the correct variable in throw

Author: diemol

java/src/org/openqa/selenium/grid/node/local/LocalNode.java

@@ -899,11 +899,11 @@ private Session createExternalSession(
     boolean bidiSupported = isSupportingBiDi && (webSocketUrl instanceof String);
     if (bidiSupported && bidiEnabled) {
       String biDiUrl = (String) other.getCapabilities().getCapability("webSocketUrl");
-      URI uri = null;
+      URI uri;
       try {
         uri = new URI(biDiUrl);
       } catch (URISyntaxException e) {
-        throw new IllegalArgumentException("Unable to create URI from " + uri);
+        throw new IllegalArgumentException("Unable to create URI from " + biDiUrl);
       }
       String bidiPath = String.format("/session/%s/se/bidi", other.getId());
       toUse =