Add missing typer dependency

[longzheng]

Running the CLI without has an error

C:\Users\longz\Documents\GitHub\SEP2-Tools>sep2tools
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\longz\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\Scripts\sep2tools.exe\__main__.py", line 4, in <module>
  File "C:\Users\longz\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\sep2tools\cli.py", line 4, in <module>
    import typer
ModuleNotFoundError: No module named 'typer'

[aguinane]

These are failing due to some fixes I've implemented on another branch to get actions working. I'll add typer on that one.