fix action

Author: bertmelis

.github/workflows/build_platformio.yml

@@ -29,7 +29,7 @@ jobs:
     strategy:
       matrix:
         example: [
-          examples/generic-interface/generic-interface.ino
+          examples/generic-interface/generic-interface.ino,
           examples/simple-read-VS1/simple-read-VS1.ino,
           examples/simple-read-VS2/simple-read-VS2.ino,
           examples/simple-write-VS1/simple-write-VS1.ino,