[SCB-1297] NPE would be arised if you haven't set any value for servicecomb.config.ignoreResolveFailure

[HuaiJoe]

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[yhs0092]

Hi, the CI seems fail. Could you fix it? You can run the integration test by running mvn clean install -Pit in the root directory of the project. And the IT requires a local service-center running in your development environment.
And it's suggested that the jira issue Key should be added into the commit message as prefix. You can see the commit message format in the former PR of this issue : )