chore: update actions config to avoid deprecation warnings

    Node.js 12 actions are deprecated. For more information see:
    https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.
    Please update the following actions to use Node.js 16:
    actions/checkout@v2,
    actionsx/prettier@v2,
    JohnnyMorganz/stylua-action@1.0.0

    ubuntu-latest workflows will use ubuntu-22.04 soon. For more details,
    see actions/runner-images#6399

No new release of `actionsx/prettier` action yet, but I updated the
others.

.github/workflows/lua.yml

@@ -10,11 +10,11 @@ on:
 
 jobs:
   style:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v2
-      - uses: JohnnyMorganz/stylua-action@1.0.0
+      - uses: actions/checkout@v3
+      - uses: JohnnyMorganz/stylua-action@v2
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           args: --check .
@@ -25,10 +25,10 @@ jobs:
           check-path: lua
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: leafo/gh-actions-lua@v9
         with:
           luaVersion: luajit-2.1.0-beta3

.github/workflows/prettier.yml

@@ -10,10 +10,10 @@ on:
 
 jobs:
   style:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: actionsx/prettier@v2
         with:
           args: --list-different "**/*.md"

.github/workflows/ruby.yaml

@@ -10,20 +10,20 @@ on:
 
 jobs:
   style:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: jidicula/clang-format-action@v4.8.0
         with:
           clang-format-version: "14"
           check-path: ruby
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Install libraries
         run: |
           set -x