DbxClientTest: Fix month number in test folder name (was using "mm" instead of "MM").
DbxClientTest: Fix month number in test folder name (was using "mm" instead of "MM").

septo13/dropbox-sdk-java,ipmobiletech/dropbox-sdk-java,dropbox/dropbox-sdk-java,ipmobiletech/dropbox-sdk-java,andyjagoe/dropbox-sdk-java,hunchee/dropbox-sdk-java,dropbox/dropbox-sdk-java,dropbox/dropbox-sdk-java,hunchee/dropbox-sdk-java,andyjagoe/dropbox-sdk-java,septo13/dropbox-sdk-java,d1nsh/dropbox-sdk-java,d1nsh/dropbox-sdk-java,dropbox/dropbox-sdk-java