Update makefile clean commands

Makefile

@@ -1,21 +1,22 @@
 .PHONY: clean build docs
 
 clean: # clean all build, python, and testing files
-	rm -fr build/
-	rm -fr dist/
-	rm -fr .eggs/
-	find . -name '*.egg-info' -exec rm -fr {} +
-	find . -name '*.egg' -exec rm -f {} +
+	rm -rf build/
+	rm -rf dist/
+	rm -rf .eggs/
+	find . -name '*.egg-info' -exec rm -rf {} +
+	find . -name '*.egg' -exec rm -rf {} +
 	find . -name '*.pyc' -exec rm -f {} +
 	find . -name '*.pyo' -exec rm -f {} +
 	find . -name '*~' -exec rm -f {} +
 	find . -name '__pycache__' -exec rm -fr {} +
-	rm -fr .tox/
-	rm -fr .coverage
-	rm -fr coverage.xml
-	rm -fr htmlcov/
-	rm -fr .pytest_cache
-	rm -fr .mypy_cache
+	rm -rf .tox/
+	rm -rf .coverage
+	rm -rf coverage.xml
+	rm -rf htmlcov/
+	rm -rf .pytest_cache
+	rm -rf .mypy_cache
+	rm -rf .ruff_cache
 
 build: # run tox tests and lint
 	tox