git hook file change tracker added

It works After the merge (post-merge)

Sample;
case: if dockerfile changed then rebuild docker container

1.) open ./scripts/file-watcher.sh
2.) add this code to the last line of file
    ```
    # $1 descdescription
    # $2 tracked file
    # $3 action
    check_run "Main dockerfile" "dockerfile" "docker-compose build";
    ```

Author: syy