Remove constraint for tox<4 for test suite

Author: johannaengland

.github/workflows/tests.yml

@@ -47,7 +47,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          python -m pip install "tox<4" tox-gh-actions coverage
+          python -m pip install tox tox-gh-actions coverage
           sudo apt-get install -y --no-install-recommends snmp libsnmp-dev
 
       - name: Test with tox

requirements/dev.txt

@@ -14,5 +14,5 @@ retry
 ruff
 snmpsim>=1.0,!=1.1.6
 towncrier
-tox<4
+tox
 twine