[main] GitHub actions and style checks: bump some versions

Use newer Linux (Ubuntu 22.04) and Python (3.10) versions for the GitHub
Action style checks, and update the PyYAML version used by the style
checks to the current default version on Ubuntu 22.04.

We are making this change because the GitHub actions currently fail
when trying to install PyYAML.

.github/workflows/style.yml

@@ -10,15 +10,15 @@ on:
 jobs:
   style:
     name: Test code style
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Clone repository
         uses: actions/checkout@master
 
       - name: Install Python
         uses: actions/setup-python@master
         with:
-          python-version: 3.8
+          python-version: 3.10
 
       - name: Install dependencies
         run: |

misc/tox.ini

@@ -72,7 +72,7 @@ commands =
 
 [testenv:clang-tidy]
 changedir = {toxinidir}/style/
-deps = PyYAML==3.12
+deps = PyYAML==5.4
 commands =
   python run-clang-tidy.py