Updated ProjectListItem.jsx for GCP files

I have updated the accepted file types to include the gcp_list.txt files so that gcp_list.txt files can be accepted. I have purposely not add all .txt files so that only the correct file name is accepted, else this will fail when it runs.

app/static/app/js/components/ProjectListItem.jsx

@@ -95,7 +95,7 @@ class ProjectListItem extends React.Component {
         url : `/api/projects/${this.state.data.id}/tasks/`,
         parallelUploads: 9999999,
         uploadMultiple: true,
-        acceptedFiles: "image/*",
+        acceptedFiles: "image/*,gcp_list.txt",
         autoProcessQueue: true,
         createImageThumbnails: false,
         clickable: this.uploadButton,