Add ruff workflow. update README

.github/workflows/ruff.yml

@@ -0,0 +1,8 @@
+name: Ruff
+on: [push, pull_request]
+jobs:
+  ruff:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/ruff-action@v1

README.md

@@ -5,7 +5,7 @@
 ## Getting started
 
 ### System requirements
-copairs supports Python 3.9+ and should work with all modern operating systems (tested with MacOS 13.5, Ubuntu 18.04, Windows 10).
+copairs supports Python 3.8+ and should work with all modern operating systems (tested with MacOS 13.5, Ubuntu 18.04, Windows 10).
 
 ### Dependencies
 copairs depends on widely used Python packages:
@@ -31,8 +31,7 @@ pip install copairs[demo]
 
 To run tests, run:
 ```bash
-pip install pytest scikit-learn
-cd copairs
+pip install -e .[test]
 pytest
 ```
 
@@ -58,4 +57,4 @@ BibTeX:
   year={2024},
   doi={10.1101/2024.04.01.587631}
 }
-```
+```