IsADirectoryError with v4.3.1

[martincostello]

          I'm still seeing this issue with the latest release of the action - when is a new version of the action with the fix going to be released?

Originally posted by @martincostello in #1303 (comment)

See here for example:

Traceback (most recent call last):
  File "codecov_cli/main.py", line 83, in <module>
  File "codecov_cli/main.py", line 79, in run
  File "click/core.py", line 1157, in __call__
  File "click/core.py", line 10[78](https://github.com/App-vNext/Polly/actions/runs/9060758833/job/24891128906#step:8:79), in main
  File "click/core.py", line 1688, in invoke
  File "click/core.py", line 1434, in invoke
  File "click/core.py", line 783, in invoke
  File "click/decorators.py", line 33, in new_func
  File "codecov_cli/commands/upload.py", line 257, in do_upload
  File "codecov_cli/services/upload/__init__.py", line 112, in do_upload_logic
  File "codecov_cli/services/upload/upload_sender.py", line 81, in send_upload_data
  File "codecov_cli/services/upload/upload_sender.py", line 121, in _generate_payload
  File "codecov_cli/services/upload/upload_sender.py", line 161, in _get_files
  File "codecov_cli/services/upload/upload_sender.py", line 161, in <listcomp>
  File "codecov_cli/services/upload/upload_sender.py", line 164, in _format_file
  File "codecov_cli/services/upload/upload_sender.py", line 175, in _get_format_info
  File "codecov_cli/types.py", line 14, in get_content
IsADirectoryError: [Errno 21] Is a directory: '.'
```Traceback (most recent call last):
  File "codecov_cli/main.py", line 83, in <module>
  File "codecov_cli/main.py", line 79, in run
  File "click/core.py", line 1157, in __call__
  File "click/core.py", line 1078, in main
  File "click/core.py", line 1688, in invoke
  File "click/core.py", line 1434, in invoke
  File "click/core.py", line 783, in invoke
  File "click/decorators.py", line 33, in new_func
  File "codecov_cli/commands/upload.py", line 257, in do_upload
  File "codecov_cli/services/upload/__init__.py", line 112, in do_upload_logic
  File "codecov_cli/services/upload/upload_sender.py", line 81, in send_upload_data
  File "codecov_cli/services/upload/upload_sender.py", line 121, in _generate_payload
  File "codecov_cli/services/upload/upload_sender.py", line 161, in _get_files
  File "codecov_cli/services/upload/upload_sender.py", line 161, in <listcomp>
  File "codecov_cli/services/upload/upload_sender.py", line 164, in _format_file
  File "codecov_cli/services/upload/upload_sender.py", line 175, in _get_format_info
  File "codecov_cli/types.py", line 14, in get_content
IsADirectoryError: [Errno 21] Is a directory: '.'