Use correct value for JAVA_HOME in Kokoro macOS scripts

PiperOrigin-RevId: 597247159
Change-Id: I78b6bfcb20f12c0e5a5e0297444b222b33524ad5

kokoro/macos_external/bazel/run_tests.sh

@@ -24,7 +24,7 @@ export COURSIER_OPTS="-Djava.net.preferIPv6Addresses=true"
 if [[ -n "${KOKORO_ROOT:-}" ]] ; then
   readonly TINK_BASE_DIR="$(echo "${KOKORO_ARTIFACTS_DIR}"/git*)"
   cd "${TINK_BASE_DIR}/tink_java_awskms"
-  export JAVA_HOME=$(/usr/libexec/java_home -v "1.8.0_292")
+  export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-8-latest/Contents/Home
 fi
 
 ./kokoro/testutils/update_android_sdk.sh