This reverts commit 673e8b5e.

* JENKINS-35198 Add failing test for clear identification of the issue and future regression test

* JENKINS-35198 Fix DelegatingComputerLauncher logic for filtering out subclasses as possible delegates

this logic is by default, and subclasses can still allow the selection of other DelegatingComputerLauncher instances as delegates.

Updated Polish translations

Fixes Jenkins build error

contains fixes for GROOVY-7761 and GROOVY-7826

[FIXES JENKINS-34751]

* [JENKINS-35020] Fixed some JSHint errors

* [JENKINS-35020] @kzantow's comment was addressed

* [JENKINS-35020] @kzantow's comment was addressed

[FIXED JENKINS-34883] the legacy default update site can be different from the one specified by ID_DEFAULT

* JENKINS-34708 - UpdateCenter.EnableJob not properly setting status

* Restore if (status instanceof Pending)

* [JENKINS-31417] CLI command connect-node extracted from core to CLI

connect-node extended to accept multiple node names
connect-node covered by test-cases

* Slighty modified Javadoc

* Fixed translations after rebase

* [JENKINS-34531] Extended CLI online-node for accepting multiple agents

Polished and extended related TC as well.

* Simplified string composition

* Simplified initialization of HashSet

[FIXED JENKINS-34880] do not show warnings if tool installer is present in at least 1 update site (#2361)

* [JENKINS-34854] - Migrate missing Integer and Boolean properties to SystemProperties

* [JENKINS-34854] - API methods for Long variables

* [JENKINS-34854] - Migrate Long settings to SystemProperties

* [JENKINS-34854] - Leftover change (I should use Save All)

* [JENKINS-34854] - Some fixes in Long methods Javadoc and log messages

* [JENKINS-34244] Some UX improvements in the New item form
* [JENKINS-34244] Submit button has three-state behavior
* [JENKINS-34244] New helper methods were added to make easier the form validation. Focus behavior reviewed

* Handle legacy use of iconSize as a variable

When iconSize was set as a jelly variable, not passed as an attribute,
the value was not being normalized to an IconSizeClass. Fixes
JENKINS-25220.

* Evaluate attrs.iconSize explicitly.

[JENKINS-33663] - Upgrade wizard

Add Upgrade Wizard
Add 'replace' handlebars method in jenkins.js
Fix state transitions to follow a single basic pattern
Suggested plugins selected by default
Add an install state for INITIAL_SECURITY_SETUP
Removed duplicate setupWizard.js on page [FIX JENKINS-34676]
Exclude plugins which are already installed when determining platform
Change 'snooze' to not look like a 'close' button
Make sure unlock screen doesn't show up after new install
Add compatibility check when offering suggested plugins
More appropriate handling of security token filter

[JENKINS-34858] - Listed Parameters should reflect what was used when the build ran

[FIXED JENKINS-34883] the legacy default update site can be different from the one specified by ID_DEFAULT

- [x] - Avoid String concatenation
- [x] - Switch to R/W lock instead of the specialized container with a significant overhead