ci: switch from bandit/flake8/pylint to ruff in CI for Python scripts

.github/workflows/ci.yml

@@ -18,7 +18,6 @@ env:
     curl
     devscripts
     equivs
-    flake8
     gem2deb
     guile-3.0-dev
     lcov
@@ -40,8 +39,6 @@ env:
     php-dev
     pipx
     pkgconf
-    pylint
-    python3-bandit
     python3-dev
     ruby-pygments.rb
     shellcheck
@@ -158,7 +155,7 @@ jobs:
         sudo apt-get --yes --no-install-recommends install ${{ env.WEECHAT_DEPS_UBUNTU }}
         # uninstall php imagick as is causes a crash when loading php plugin (see #2009)
         sudo apt-get --yes purge php8.3-imagick
-        pipx install msgcheck schemathesis
+        pipx install msgcheck ruff schemathesis
 
     - name: Check gettext files
       run: msgcheck po/*.po