cln4rust: crashing while installing the log

```
thread 'main' panicked at /home/vincent/.cargo/git/checkouts/cln4rust-0de0305144cd79e4/56b385f/plugin/src/plugin.rs:268:55:
called `Result::unwrap()` on an `Err` value: ParseLevelError(())
stack backtrace:
0: rust_begin_unwind
at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panicking.rs:645:5
1: core::panicking::panic_fmt
at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/panicking.rs:72:14
2: core::result::unwrap_failed
at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/result.rs:1654:5
3: core::result::Result::unwrap
at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/result.rs:1077:23
4: clightningrpc_plugin::plugin::Plugin::start
at /home/vincent/.cargo/git/checkouts/cln4rust-0de0305144cd79e4/56b385f/plugin/src/plugin.rs:268:25
5: barq_plugin::main
at /home/vincent/github/work/sob2024/barq/barq-plugin/src/main.rs:9:5
6: core::ops::function::FnOnce::call_once
at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
lightningd: FATAL SIGNAL 11 (version v24.05)
0x48452d send_backtrace
???:0
0x4845c3 crashdump
???:0
0x7ffff7b8bf3f ???
???:0
0x455d24 plugin_conn_finish
???:0
0x55aca0 destroy_conn
???:0
0x55acc2 destroy_conn_close_fd
???:0
0x564b35 notify
???:0
0x564c0d del_tree
???:0
0x565112 tal_free
???:0
0x55993d io_close
???:0
0x55b2c0 io_loop
???:0
0x42afcf io_loop_with_timers
???:0
0x457987 plugins_init
???:0
0x430084 main
???:0
0x7ffff7b7610d __libc_start_call_main
???:0
0x7ffff7b761c8 __libc_start_main_alias_1
???:0
0x405d64 _start
???:0
0xffffffffffffffff ???
???:0
Time-out: can't find [re.compile('Server started with public key')] in logs
FLeaving base_dir /tmp/ltests-5o5n_l48 intact, it still has test sub-directories with failure details: ['test_init_1']
E
```

Please the plugin code should compile if we revert the following commit https://github.com/tareknaser/barq/pull/4/commits/986557981386ee7e58f626d5418476316868d051

Start at barq-plugin/src/main.rs:9 and inspect the panic reported at plugin.rs:268 in the cln4rust checkout. Compare the plugin with commit 986557981386ee7e58f626d5418476316868d051 and verify that installation no longer produces the ParseLevelError panic or the failed startup-log check.

Written by the indexing model from the issue text.