fix(ci): disable Gradle build cache for Kotlin SDK in Java E2E

Self-hosted runner's persisted build cache can serve stale class files
from a previous branch, causing compilation errors when new methods
(e.g. manualCleanup) are not found. Clean and disable build cache
to ensure a fresh build every run.

Made-with: Cursor

Author: hittyt

scripts/java-e2e.sh

@@ -52,11 +52,11 @@ cd ..
 sleep 10
 
 cd sdks/sandbox/kotlin
-./gradlew publishToMavenLocal
+./gradlew clean publishToMavenLocal --no-build-cache
 cd ../../../
 
 cd sdks/code-interpreter/kotlin
-./gradlew publishToMavenLocal -PuseMavenLocal
+./gradlew clean publishToMavenLocal --no-build-cache -PuseMavenLocal
 cd ../../../
 
 # run Java e2e