Fix ProviderTest.itCanDoAValueEvaluation race condition on Java 11

Add Awaitility.await() guard before asserting on getObjectValue result,
matching the pattern used by the other evaluation tests (boolean, string,
double). Without this, setProvider (non-blocking) may not have completed
by the time getObjectValue is called, returning the default Value() whose
asStructure() is null — causing a NullPointerException on Java 11.

Co-Authored-By: rlamb@launchdarkly.com <kingdewman@gmail.com>

Author: devin-ai-integration[bot]

src/test/java/com/launchdarkly/openfeature/serverprovider/ProviderTest.java

@@ -128,6 +128,13 @@ public void itCanDoAValueEvaluation() {
             .thenReturn(evaluationDetail);
 
         OpenFeatureAPI.getInstance().setProvider(ldProvider);
+
+        Awaitility.await().forever().until(() -> {
+            Value val = OpenFeatureAPI.getInstance().getClient()
+                .getObjectValue("the-key", new Value(), evaluationContext);
+            return val != null && val.asStructure() != null;
+        });
+
         Value ofValue = OpenFeatureAPI
             .getInstance()
             .getClient()