feat: add an option to automatically delete a temporal entity when corresponding entity is deleted

- `context_server_host` and `context_server_port` : The address and port used for the context server provider. 

Default value: `0.0.0.0` and `8087`.

- `core_context`: The default cached core context used by the Brokers.

- `delete_temporal_on_core_delete`: Whether the Temporal Representation of an Entity should be deleted when an Entity is deleted.

Default value: True

When you execute locally the tests, you can leave the default values as they are. NGSI-LD Test Suite provides

a mockup services to provide the notification functionality and therefore the notification_server_host can be

Library         OperatingSystem

Library         Collections

Library         JSONLibrary

Resource        ${EXECDIR}/resources/ApiUtils/TemporalContextInformationProvision.resource

Resource        ${EXECDIR}/resources/JsonUtils.resource

    ${response}=    DELETE

    ...    url=${base_url}/${ENTITIES_ENDPOINT_PATH}${id}

    ...    expected_status=any

    IF    ${delete_temporal_on_core_delete}

        Delete Temporal Representation Of Entity    ${id}

    END

    Output    ${response}    Delete Entity by Id

    RETURN    ${response}

context_server_port = 8087

core_context = 'https://uri.etsi.org/ngsi-ld/v1/ngsi-ld-core-context-v1.6.jsonld'

# whether the Temporal Representation of an Entity should be deleted when an Entity is deleted

delete_temporal_on_core_delete = True

#DistOps variables

remote_url = 'http://0.0.0.0:8081/ngsi-ld/v1'

context_source_endpoint  = 'http://0.0.0.0:8081'