Fix flaky PulsarFunctionAdministrationIntegrationTests

Pause after context close to give stop policies time to execute

spring-pulsar-spring-boot-autoconfigure/src/test/java/org/springframework/pulsar/autoconfigure/PulsarFunctionAdministrationIntegrationTests.java

@@ -162,6 +162,9 @@ class PulsarFunctionAdministrationIntegrationTests {
 			}
 		}
 
+		// Give functions time to invoke stop policy after context close
+		Thread.sleep(10000);
+
 		// Stop policy runs after context close - verify source are in expected state
 		try (PulsarAdmin admin = getAdmin()) {
 			assertSourceExistsWithStatus("rabbit-test-source-none", true, admin);