Dev230321

Dear @philipp.sommer

I resolved issue #15 (closed), and created a search function using Select2, for FilePathFields. Nevertheless, since Selec2 was created to be able to search across ForeignKey and M2M fields, I developed certain portions in JS files. On the other hand, because Select2 didn't support nested_inlines, I modified the JS files once again and included them as static files to MDE Thredds. It should be mentioned that I opened some issues regarding these problems in Select2 repositories in GitHub, but because I didn't have any access to their repo to push to new branch there, and didn't get any response, I did it by myself in our repo in Helmholtz GitLab.