Java 21 [#96932](https://github.com/elastic/elasticsearch/pull/96932) (`-Druntime.java=21`) breaks `java.util.List` lookups in Painless scripts.

```
invalid foreach loop: method [java.util.List, iterator/0] not found
member method [java.util.List, add/1] not found
member method [java.util.List, asCollection/0] not found
member method [java.util.List, asList/0] not found
member method [java.util.List, isEmpty/0] not found
member method [java.util.List, size/0] not found
member method [java.util.List, stream/0] not found
```

`:modules:lang-painless:test` (57 failures): https://gradle-enterprise.elastic.co/s/dkpi5pcitruwy
`:modules:lang-painless:yamlRestTest` (6 failures) https://gradle-enterprise.elastic.co/s/rsf3522r44ilc

```
java -version
openjdk version "21-ea" 2023-09-19
OpenJDK Runtime Environment (build 21-ea+27-2343)
OpenJDK 64-Bit Server VM (build 21-ea+27-2343, mixed mode, sharing)
```

Refs: https://github.com/elastic/elasticsearch/issues/96997
modules/lang-painless/src/main/java/org/elasticsearch/painless/lookup/PainlessLookup.java
}
    public PainlessMethod lookupImportedPainlessMethod(String methodName, int arity) {
        Objects.requireNonNull(methodName);
        String painlessMethodKey = buildPainlessMethodKey(methodName, arity);
        return painlessMethodKeysToImportedPainlessMethods.get(painlessMethodKey);
    }
    public PainlessClassBinding lookupPainlessClassBinding(String methodName, int arity) {
        Objects.requireNonNull(methodName);
        String painlessMethodKey = buildPainlessMethodKey(methodName, arity);
        return painlessMethodKeysToPainlessClassBindings.get(painlessMethodKey);
    }
    public PainlessInstanceBinding lookupPainlessInstanceBinding(String methodName, int arity) {
        Objects.requireNonNull(methodName);
        String painlessMethodKey = buildPainlessMethodKey(methodName, arity);
        return painlessMethodKeysToPainlessInstanceBindings.get(painlessMethodKey);
    }
    public PainlessMethod lookupFunctionalInterfacePainlessMethod(Class<?> targetClass) {
        PainlessClass targetPainlessClass = classesToPainlessClasses.get(targetClass);
        if (targetPainlessClass == null) {
            return null;
        }
        return targetPainlessClass.functionalInterfaceMethod;
    }
    public PainlessMethod lookupRuntimePainlessMethod(Class<?> originalTargetClass, String methodName, int methodArity) {
        Objects.requireNonNull(originalTargetClass);
        Objects.requireNonNull(methodName);
        String painlessMethodKey = buildPainlessMethodKey(methodName, methodArity);
        Function<PainlessClass, PainlessMethod> objectLookup = targetPainlessClass -> targetPainlessClass.runtimeMethods.get(
            painlessMethodKey
        );