inplace of hasSize(0), isEmpty() is used in AssertJ for better error message

https://sonarcloud.io/project/issues?resolved=false&severities=MINOR&id=onap_vnfsdk-validation

Issue-ID: VNFSDK-832

Signed-off-by: prakash.e@huawei.com <prakash.e@huawei.com>
Change-Id: Ida0d4a2283e500e553b0886b666e5997cf52b7fc
1 file changed