bump codecov CI

Author: exaexa

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ jobs:
       matrix:
         version:
           - '1' # This is always the latest stable release in the 1.X series
-          #- '1.6' # LTS
+          - '1.6' # LTS
           #- 'nightly'
         os:
           - ubuntu-latest
@@ -37,6 +37,7 @@ jobs:
       - uses: julia-actions/julia-runtest@latest
         continue-on-error: ${{ matrix.version == 'nightly' }}
       - uses: julia-actions/julia-processcoverage@v1
-      - uses: codecov/codecov-action@v3
+      - uses: codecov/codecov-action@v4
         with:
-          file: lcov.info
+          files: lcov.info
+          token: ${{ secrets.CODECOV_TOKEN }}