Fix test_set_time and test_time_tz's timezone error

[XuQianJin-Stars]

I encountered the following two time zone inconsistency errors while testing TestDuckDBJDBC in GMT+8:

TestDuckDBJDBC#test_set_time failed with java.lang.Exception: "04:40:00" (of class java.sql.Time) should equal "12:40:00" (of class java.sql.Time)
java.lang.Exception: "04:40:00" (of class java.sql.Time) should equal "12:40:00" (of class java.sql.Time)
        at org.duckdb.test.Assertions.assertTrue(Assertions.java:15)
        at org.duckdb.test.Assertions.assertEquals(Assertions.java:32)
        at org.duckdb.test.Assertions.assertEquals(Assertions.java:24)
        at org.duckdb.TestDuckDBJDBC.test_set_time(TestDuckDBJDBC.java:1157)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.duckdb.test.Runner.runTests(Runner.java:45)
        at org.duckdb.TestDuckDBJDBC.main(TestDuckDBJDBC.java:4310)

TestDuckDBJDBC#test_time_tz failed with java.lang.Exception: "01:01+08:00" (of class java.time.OffsetTime) should equal "01:01Z" (of class java.time.OffsetTime)
java.lang.Exception: "01:01+08:00" (of class java.time.OffsetTime) should equal "01:01Z" (of class java.time.OffsetTime)
        at org.duckdb.test.Assertions.assertTrue(Assertions.java:15)
        at org.duckdb.test.Assertions.assertEquals(Assertions.java:32)
        at org.duckdb.test.Assertions.assertEquals(Assertions.java:24)
        at org.duckdb.TestDuckDBJDBC.test_time_tz(TestDuckDBJDBC.java:1921)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.duckdb.test.Runner.runTests(Runner.java:45)
        at org.duckdb.TestDuckDBJDBC.main(TestDuckDBJDBC.java:4310)

[Mause]

Thanks!