Ensure correct this context for addMembership function to call the blur method correctly. Fixes #10555 (#10560)

* Pass the  reference explicitly to the  function to ensure the correct context is available.

* refactor: handle blur() in a closure to separate UI logic from addMembership

* spacing

* Fixed typo

---------

Co-authored-by: Deeptanshu Sankhwar <deeptanshu@walletsocket.com>
Co-authored-by: Minh Nguyễn <mxn@1ec5.org>

modules/ui/sections/raw_membership_editor.js

@@ -171,7 +171,6 @@ export function uiSectionRawMembershipEditor(context) {
 
 
     function addMembership(d, role) {
-        this.blur();           // avoid keeping focus on the button
         _showBlank = false;
 
         function actionAddMembers(relationId, ids, role) {
@@ -502,7 +501,10 @@ export function uiSectionRawMembershipEditor(context) {
         newMembership.selectAll('.member-entity-input')
             .on('blur', cancelEntity)   // if it wasn't accepted normally, cancel it
             .call(nearbyCombo
-                .on('accept', acceptEntity)
+                .on('accept', function(d) {
+                    this.blur(); // always blurs the triggering element
+                    acceptEntity.call(this, d);
+                })
                 .on('cancel', cancelEntity)
             );