Clear the "unused" version number in pyproject.toml to develop

The version number committed is never actually used to push anything to PyPI, as `poetry version <tag version>` is run by the Publish Github Actions workflow. This change hopefully makes confusion about this fact less likely.

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "gatorgrader"
-version = "1.1.0"
+version = "develop"
 description = "Automated Grading Tool that Checks the Work of Writers and Programmers"
 authors = ["Gregory Kapfhammer <[email protected]>"]
 license = "GPL-3.0"