Mobile fix for Project view: Add delay to Sortable.js on mobile, to ensure scrolling is possible. (#22152)

Mobile / touch devices currently get "hung up" on the sortable action,
preventing any ability to visually scroll through the Project board to
see issues.

Solution: Sortable.js has a built-in fix using `delayOnTouchOnly`

BEFORE

https://user-images.githubusercontent.com/24665/208266817-6f2968b7-4788-4656-a941-f85b25fc59d5.mp4

AFTER

https://user-images.githubusercontent.com/24665/208266822-3d327002-7a9d-41cf-9890-6d6b8dcb17be.mp4

Co-authored-by: Lunny Xiao <[email protected]>
Co-authored-by: techknowlogick <[email protected]>

Author: 3 people

web_src/js/features/repo-projects.js

@@ -49,6 +49,8 @@ async function initRepoProjectSortable() {
     filter: '[data-id="0"]',
     animation: 150,
     ghostClass: 'card-ghost',
+    delayOnTouchOnly: true,
+    delay: 500,
     onSort: () => {
       boardColumns = mainBoard.getElementsByClassName('board-column');
       for (let i = 0; i < boardColumns.length; i++) {
@@ -76,6 +78,8 @@ async function initRepoProjectSortable() {
       ghostClass: 'card-ghost',
       onAdd: moveIssue,
       onUpdate: moveIssue,
+      delayOnTouchOnly: true,
+      delay: 500,
     });
   }
 }