Version bump all GHA actions to remove node.js v16 warning.

Warning message from GHA before version bump:
```
Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v3, actions/setup-python@v3, actions/cache@v3. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.
```

.github/workflows/build.yml

@@ -18,12 +18,12 @@ jobs:
       COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 1
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v3
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
           cache: pip
@@ -35,7 +35,7 @@ jobs:
         run: tox
 
       - name: cache deps
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.tox
           key: deps-${{ hashFiles('**/pyproject.toml') }}

.github/workflows/pre-release.yml

@@ -8,10 +8,10 @@ jobs:
   deploy:
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v3
+        uses: actions/setup-python@v5
         with:
           python-version: "3.x"
           cache: pip

.github/workflows/release.yml

@@ -8,10 +8,10 @@ jobs:
   deploy:
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v3
+        uses: actions/setup-python@v5
         with:
           python-version: "3.x"
           cache: pip