bp #41956
This PR #40225 try to pass time zone info from BE to JNI, and it use
`_state->timezone_obj().name()`
to get the timezone name.
But when we do some rolling upgrade of BE, it may coredump like:
```
*** SIGSEGV address not mapped to object (@0x610) received by PID 72661 (TID 73538 OR 0x7f2e898d1640) from PID 1552; stack trace: ***
0# doris::signal::(anonymous namespace)::FailureSignalHandler(int, siginfo_t*, void*) at /home/zcp/repo_center/doris_branch-2.1/doris/be/src/common/signal_handler.h:421
1# os::Linux::chained_handler(int, siginfo_t*, void*) in /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/amd64/server/libjvm.so
2# JVM_handle_linux_signal in /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/amd64/server/libjvm.so
3# signalHandler(int, siginfo_t*, void*) in /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/amd64/server/libjvm.so
4# 0x00007F3070D3E520 in /lib/x86_64-linux-gnu/libc.so.6
5# cctz::time_zone::name[abi:cxx11]() const in /mnt/hdd01/ci/compatibility-deploy/be/lib/doris_be
6# doris::vectorized::JniConnector::open(doris::RuntimeState*, doris::RuntimeProfile*) at /home/zcp/repo_center/doris_branch-2.1/doris/be/src/vec/exec/jni_connector.cpp:87
7# doris::vectorized::AvroJNIReader::init_fetch_table_schema_reader() at /home/zcp/repo_center/doris_branch-2.1/doris/be/src/vec/exec/format/avro/avro_jni_reader.cpp:119
8# std::_Function_handler::_M_invoke(std::_Any_data const&) at /var/local/ldb-toolchain/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_function.h:291
9# doris::WorkThreadPool::work_thread(int) at /home/zcp/repo_center/doris_branch-2.1/doris/be/src/util/work_thread_pool.hpp:159
10# execute_native_thread_routine at ../../../../../libstdc++-v3/src/c++11/thread.cc:84
11# start_thread at ./nptl/pthread_create.c:442
12# 0x00007F3070E22850 at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:83
172.20.50.206 last coredump sql: 2024-10-13 04:12:23,985 [query]
```
This PR use another method: `_state->timezone()`, which just return a
string, instead of reading and initializing
time zone info file, to avoid potential coredump.
b4875c2789