fix!: allow system managers to toggle email queue

[sagarvora]

Closes #14218

Why did the Resume / Suspend Sending button only work for Administrator?

The button set the default hold_queue using the frappe.defaults.set_default JS API which called the frappe.client.set_default API without explicitly passing a parent. In absence of a parent, the set_default API chose frappe.session.user as one (why?). When processing the queue in EmailQueue.process, we're using frappe.defaults.get_defaults which gets defaults from the __default + frappe.session.user parents. When called from redis queue, the frappe.session.user is Administrator. Hence, get_defaults gives the correct value of hold_queue only if set by Administrator, but not other users.

Changes Made

• BREAKING: remove frappe.client.set_default and the corresponding frappe.default.set_default API. Shouldn't affect a lot of users:
  https://sourcegraph.com/search?q=context:global+frappe.client.set_default&patternType=literal
  https://sourcegraph.com/search?q=context:global+frappe.defaults.set_default+lang:javascript+&patternType=literal

• New whitelisted method for System Managers to toggle sending - corresponding implementation in email_queue_list.js

• The toggle between List View and other views wasn't showing before due to call of clear_inner_toolbar - fixed.

• Use frappe.db.get_default instead of frappe.defaults.get_defaults when checking hold_queue.

• Patch to set hold_queue in the __default parent instead of Administrator, and to remove the default from all other user parents.

• Update existing whitelisted methods to check permission.

Screenshots

Patch Test

UI

[codecov]

Codecov Report

Merging #17466 (4b0a9da) into develop (04f4fd8) will increase coverage by 0.37%.
The diff coverage is 50.00%.

@@             Coverage Diff             @@
##           develop   #17466      +/-   ##
===========================================
+ Coverage    56.62%   57.00%   +0.37%     
===========================================
  Files          760      768       +8     
  Lines        68219    69016     +797     
  Branches      5835     6003     +168     
===========================================
+ Hits         38632    39343     +711     
- Misses       25946    26192     +246     
+ Partials      3641     3481     -160     

Flag	Coverage Δ
server	61.14% <50.00%> (-1.76%)	⬇️
ui-tests	49.76% <ø> (+4.45%)	⬆️

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[sagarvora]

@Mergifyio backport version-13-hotfix

[mergify]

backport version-13-hotfix

✅ Backports have been created

• #17539 fix!: allow system managers to toggle email queue (backport #17466) has been created for branch version-13-hotfix