GHA: Fix codecov action file->files (#2666)

Options changed in https://github.com/codecov/codecov-action v5.

Author: dweindl

.github/workflows/test_benchmark_collection_models.yml

@@ -77,7 +77,7 @@ jobs:
       uses: codecov/codecov-action@v5
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
-        file: coverage_py.xml
+        files: coverage_py.xml
         flags: python
         fail_ci_if_error: true
         verbose: true

.github/workflows/test_petab_test_suite.yml

@@ -104,6 +104,6 @@ jobs:
         uses: codecov/codecov-action@v5
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
-          file: coverage.xml
+          files: coverage.xml
           flags: petab
           fail_ci_if_error: true

.github/workflows/test_python_cplusplus.yml

@@ -82,7 +82,7 @@ jobs:
       uses: codecov/codecov-action@v5
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
-        file: build/coverage_py.xml
+        files: build/coverage_py.xml
         flags: python
         fail_ci_if_error: true
         verbose: true
@@ -102,7 +102,7 @@ jobs:
       uses: codecov/codecov-action@v5
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
-        file: coverage.info
+        files: coverage.info
         flags: cpp
         fail_ci_if_error: true
 
@@ -164,7 +164,7 @@ jobs:
       uses: codecov/codecov-action@v5
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
-        file: build/coverage_py.xml
+        files: build/coverage_py.xml
         flags: python
         fail_ci_if_error: true
         verbose: true
@@ -184,7 +184,7 @@ jobs:
       uses: codecov/codecov-action@v5
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
-        file: coverage.info
+        files: coverage.info
         flags: cpp_python
         fail_ci_if_error: true