Try Java 17 because of error "Unable to reuse same channel across requests" when using Java 21.

Author: kannanjgithub

gae-interop-testing/gae-jdk8/src/main/webapp/WEB-INF/appengine-web.xml

@@ -14,6 +14,6 @@
 <!-- [START config] -->
 <appengine-web-app xmlns='http://appengine.google.com/ns/1.0'>
   <service>java-gae-interop-test</service>
-  <runtime>java21</runtime>
+  <runtime>java17</runtime>
 </appengine-web-app>
 <!-- [END config] -->