CI: Upgrade CodeCov to v5 and use token for uploading reports.

- Upgrade Python actions to v5.
- Upgrade checkout to v4.

Author: Alir3z4

.github/workflows/main.yml

@@ -27,12 +27,12 @@ jobs:
     name: "Tox ${{ matrix.toxenv }}"
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
       - name: setup python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: '3.13'
 
@@ -72,12 +72,12 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
       - name: setup python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -88,10 +88,9 @@ jobs:
         run: tox
 
       - name: Upload coverage to Codecov
-        # see https://github.com/codecov/codecov-action/blob/master/README.md
-        uses: codecov/codecov-action@v2
+        uses: codecov/codecov-action@v5
         with:
           flags: unittests-${{ matrix.python-version }}
+          token: ${{ secrets.CODECOV_TOKEN }}
           fail_ci_if_error: true  # default = false
-          os: toxenv
           verbose: true  # default = false