Revert webdriverio to 9.15.0

Author: thomashohn

package.json

@@ -175,7 +175,7 @@
     "typedoc-plugin-markdown": "4.8.1",
     "typescript": "5.8.3",
     "wdio-docker-service": "3.2.1",
-    "webdriverio": "9.19.2",
+    "webdriverio": "9.15.0",
     "xml2js": "0.6.2",
     "xpath": "0.0.34"
   },