Remove test step since the project doesn't contain tests

.github/workflows/platform_interface_package.yaml

@@ -47,16 +47,4 @@ jobs:
       - name: Run Flutter Analyzer
         run: flutter analyze
         working-directory: ${{env.source-directory}}
-      
-      # Run all unit-tests with code coverage
-      - name: Run unit tests
-        run: flutter test --coverage
-        working-directory: ${{env.source-directory}}
-
-      # Upload code coverage information
-      - uses: codecov/codecov-action@v1
-        with:
-          file: ${{env.source-directory}}/coverage/lcov.info # optional
-          name: permission_handler_platform_interface (Platform Interface Package) # optional
-          fail_ci_if_error: true 
-  
\ No newline at end of file
+