"Apply one of the proposed measures to suppress the following error on TravisCI.

  testActionManager::test_limitCommandAction:		.: (0.094176)
[INFO] <DBClientConfig.cc:335> Configuration DB Server: localhost, port: (default), DB: hatohol, User: hatohol, use password: yes
[INFO] <DBClient.cc:200> Default DB: test_action, User: hatohol_test_user, use passowrd: no
F
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Failure: testActionManager::test_execResidentAction
Failed to connect to MySQL: (null): Lost connection to MySQL server at 'reading initial communication packet', system error: 4
./Helpers.cc:410: void makeTestMySQLDBIfNeeded(const string&, bool): cut_fail("Failed to connect to MySQL: %s: %s\n", db, mysql_error(&mysql))
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