Rename alias to run coverage discover to coverage-discover from cover…

…age.

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There are multiple options that can be executed using coverage which can be used as "pdm run coverage <options>". But by setting coverage as alias in pdm script these options were no longer excecutable since it considers the coverage as alias for command "coverage run -m unittest discover" instead of module.

pyproject.toml

@@ -62,7 +62,7 @@ downgrade = "flask db downgrade"
 test = "python -m unittest discover"
 lint = "black manage.py backend tests migrations"
 flake8 = "flake8 manage.py backend tests migrations"
-coverage = "coverage run -m unittest discover"
+coverage-discover = "coverage run -m unittest discover"
 
 [build-system]
 requires = ["pdm-pep517>=1.0.0"]