add ruff to requirements.txt (#1019)

Forgot to add this in #1016

checks-superstaq/requirements.txt

@@ -17,5 +17,6 @@ pytest-cov>=2.11.1
 pytest-randomly>=3.10.1
 pytest-socket>=0.7.0
 pytest-xdist>=3.6.1
+ruff>=0.5.6
 setuptools>=67.0.0
 sphinx-rtd-theme>=1.0.0