ci: Bump tox-lsr to 3.5.1

Drop Python 3.8, current tox-lsr does not support this any more. See
linux-system-roles/tox-lsr#178

Author: martinpitt

.github/workflows/python-unit-test.yml

@@ -21,8 +21,6 @@ jobs:
         pyver_os:
           - ver: "2.7"
             os: ubuntu-22.04
-          - ver: "3.8"
-            os: ubuntu-latest
           - ver: "3.9"
             os: ubuntu-latest
           - ver: "3.10"
@@ -65,7 +63,7 @@ jobs:
             tox=tox
             virtualenv=virtualenv
           fi
-          pip install "$tox" "$virtualenv" "git+https://github.com/linux-system-roles/tox-lsr@3.4.0"
+          pip install "$tox" "$virtualenv" "git+https://github.com/linux-system-roles/tox-lsr@3.5.1"
           # If you have additional OS dependency packages e.g. libcairo2-dev
           # then put them in .github/config/ubuntu-requirements.txt, one
           # package per line.