build(deps): bump codecov/codecov-action in the github-actions group

Bumps the github-actions group with 1 update: [codecov/codecov-action](https://github.com/codecov/codecov-action).


Updates `codecov/codecov-action` from 5 to 6
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@v5...v6)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
       - uses: ./.github/actions/go-setup
       - run: make test-codecov
       - name: Upload unit test coverage to Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           files: cov-unit-tests.out
           flags: unit-tests
@@ -31,7 +31,7 @@ jobs:
       - name: Execute OpenSearch tests
         run: make test-opensearch
       - name: Upload OpenSearch test coverage to Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           files: cov-os-tests.out
           flags: opensearch-tests
@@ -47,7 +47,7 @@ jobs:
       - name: Execute Postgres tests
         run: make test-postgres
       - name: Upload Postgres test coverage to Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           files: cov-pg-tests.out
           flags: postgres-tests