Fix ServiceConfig Ref unable to toString

[AlbumenJ]

What is the purpose of the change

Brief changelog

    @Test
    void testToString() {
        ServiceConfig<DemoService> serviceConfig = new ServiceConfig<>();
        service.setRef(new DemoServiceImpl() {
            @Override
            public String toString() {
                throw new IllegalStateException();
            }
        });
        try {
            serviceConfig.toString();
        } catch (Throwable t) {
            Assertions.fail(t);
        }
    }

Verifying this change

Checklist

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
4 Code Smells

46.6% Coverage
0.0% Duplication