adds requirements.in file for github-check.

requirements.in

@@ -0,0 +1,11 @@
+# -------------------------------------------------------------------
+# Note...
+# This project does not need any dependencies installed into a virtual environment.
+# Instead, the `self_updater.py` and `tests.py` files use the PEP-723 python `inline script metadata` syntax 
+#   to declare the dependencies. 
+#   <https://packaging.python.org/en/latest/specifications/inline-script-metadata/>
+# This allows files to be run like: `$ uv run ./tests.py`, with the python and dependencies versions being handled on-the-fly.
+# This `requirements.txt` exists only to enable GitHub's package vulnerabiiity scanner to work correctly.
+# -------------------------------------------------------------------
+
+python-dotenv~=1.0.0