Fix Pythom import errors in GDB and LLDB

```
Traceback (most recent call last):
  File "/workspaces/ChatDBG/ChatDBG/src/chatdbg/chatdbg_gdb.py", line 9, in <module>
    from . import chatdbg_utils
ImportError: attempted relative import with no known parent package
```

src/chatdbg/chatdbg_gdb.py

@@ -1,8 +1,12 @@
 import json
+import os
+import pathlib
+import sys
 
 import gdb
 
-from . import chatdbg_utils
+sys.path.append(os.path.abspath(pathlib.Path(__file__).parent.resolve()))
+import chatdbg_utils
 
 # The file produced by the panic handler if the Rust program is using the chatdbg crate.
 rust_panic_log_filename = "panic_log.txt"

src/chatdbg/chatdbg_lldb.py

@@ -1,9 +1,12 @@
-#!env python3
+import os
+import pathlib
+import sys
 from typing import Any, Optional, Tuple
 
 import lldb
 
-from . import chatdbg_utils
+sys.path.append(os.path.abspath(pathlib.Path(__file__).parent.resolve()))
+import chatdbg_utils
 
 # The file produced by the panic handler if the Rust program is using the chatdbg crate.
 rust_panic_log_filename = "panic_log.txt"