fix tests

app/src/test/java/io/swagger/client/JSONTest.java

.../java/se/leap/bitmaskclient/base/models/ProviderTest.java

...e/leap/bitmaskclient/base/utils/PreferenceHelperTest.java

app/src/test/java/se/leap/bitmaskclient/eip/GatewayTest.java

...t/java/se/leap/bitmaskclient/eip/GatewaysManagerTest.java

...ava/se/leap/bitmaskclient/eip/VpnConfigGeneratorTest.java

...p/bitmaskclient/providersetup/ProviderApiManagerTest.java

...bitmaskclient/providersetup/ProviderApiManagerV3Test.java

...leap/bitmaskclient/providersetup/ProviderManagerTest.java

...java/se/leap/bitmaskclient/testutils/TestSetupHelper.java