Fix the failing integration test and add test for File, Indexer, and Legal notifications.

provider/notification-aws/build-aws/buildspec.yaml

...fication/provider/aws/queue/NotificationQueueService.java

...ion/provider/aws/queue/NotificationRetryQueueService.java

...ation/provider/aws/queue/NotificationRetrySQSHandler.java

...tification/provider/aws/queue/NotificationSQSHandler.java

...provider/aws/queue/impl/NotificationQueueServiceImpl.java

...der/aws/queue/impl/NotificationRetryQueueServiceImpl.java

testing/notification-test-aws/build-aws/prepare-dist.sh

.../notification-test-aws/build-aws/push-endpoint/Dockerfile

...tification-test-aws/build-aws/push-endpoint/entrypoint.sh

...ation-test-aws/build-aws/push-endpoint/maven/settings.xml

...ing/notification-test-aws/build-aws/push-endpoint/pom.xml

...st-aws/build-aws/push-endpoint/setup_teardown_endpoint.py

.../push-endpoint/src/main/java/org/example/Application.java

...-endpoint/src/main/java/org/example/HmacVerification.java

...-endpoint/src/main/java/org/example/OSDUSecretString.java

...int/src/main/java/org/example/PushEndpointController.java

...-endpoint/src/main/java/org/example/QueryStringUtils.java

...sh-endpoint/src/main/java/org/example/SecurityConfig.java

...s/push-endpoint/src/main/resources/application.properties