Use github/super-linter for unused import checks

Author: Theofilos Manitaras

.github/linters/.flake8

@@ -0,0 +1,2 @@
+[flake8]
+select = F401

.github/workflows/main.yml

@@ -47,24 +47,15 @@ jobs:
       run: |
         docker run reframe:${{ matrix.modules-version }}
 
-  flake8:
-    if: github.event_name == 'pull_request'
+  unusedimports:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
       with:
         fetch-depth: 0
-    - name: Changed Python Files
-      run: |
-        echo 'CHANGED_PYTHON_FILES<<EOF' >> $GITHUB_ENV
-        git diff --name-only ${{ github.event.pull_request.base.sha }}..${{ github.sha }} | grep '.py' >> $GITHUB_ENV
-        echo 'EOF' >> $GITHUB_ENV
-    - uses: actions/setup-python@v2
-      with:
-        python-version: 3.8
-    - name: Unused Imports Check
-      run: |
-        pip install flake8
-        echo 'Checking Python Files:'
-        for f in "$CHANGED_PYTHON_FILES"; do echo "$f"; done
-        flake8 --select F401 $CHANGED_PYTHON_FILES
+    - name: Lint Code Base
+      uses: github/super-linter@v3
+      env:
+        VALIDATE_ALL_CODEBASE: false
+        VALIDATE_PYTHON_FLAKE8: true
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

README.md

@@ -3,6 +3,7 @@
 </a>
 
 [![Build Status](https://github.com/eth-cscs/reframe/workflows/ReFrame%20CI/badge.svg)](https://github.com/eth-cscs/reframe/actions?query=workflow%3A%22ReFrame+CI%22)
+[![GitHub Super-Linter](https://github.com/eth-cscs/reframe/workflows/Lint%20Code%20Base/badge.svg)](https://github.com/marketplace/actions/super-linter)
 [![Documentation Status](https://readthedocs.org/projects/reframe-hpc/badge/?version=latest)](https://reframe-hpc.readthedocs.io/en/latest/?badge=latest)
 [![codecov.io](https://codecov.io/gh/eth-cscs/reframe/branch/master/graph/badge.svg)](https://codecov.io/github/eth-cscs/reframe)<br/>
 ![GitHub release (latest by date including pre-releases)](https://img.shields.io/github/v/release/eth-cscs/reframe?include_prereleases)

setup.py

@@ -8,7 +8,7 @@
 from reframe import VERSION
 
 with open('README.md') as read_me:
-    long_description = ''.join(read_me.readlines()[15:])
+    long_description = ''.join(read_me.readlines()[16:])
 
 setuptools.setup(
     name='ReFrame-HPC',