MM-16261: Synchronize plugins in HA (#11657)

* MM-16272 - Synchronize plugins across cluster (#11611)

* MM-16272 - Synchronize plugins across cluster

* Adding a test

* MM-16272 - Fixed tests

* MM-16272 - PR feedback

* MM-16270 - Plugin Sync (#11615)

* Initial implementation for plugin synch with file store. WIP

* Removed ListAll implementation. Used ListDirectory and change localstore to be consistent and return all items (files and folders) from directory

* Refactored plugin filestore operations out of main install/remove plugin

* Fixing error handling details

* Changes to use structured logging

* More logging fixes

* Wording and comments improvements

* Error handling and control flow improvements

* Changed managed flag check to use os.stat

* Added file store plugin dir and filename consts

* Replaced FileRead to use a the FileReader in PluginSync

* Minor styling and PR feedback changes

* Minor error handling improvements

* Added unit test for SyncPlugins. Changed SyncPlugins to use plugins environment to list available plugins

* PR Feedback improvements

* Minor err handling fix

* Removing FileStorePath from PluginEventData (#11644)

* Fix plugin path (#11654)

* tweak path, logging

Fix an issue not finding the plugins folder in S3. Tweak logging messages to add additional clarity.

* Removing FileExists check when Syncing plugins. Updated localstore to not return an error when directory does not exist

* PR Feedback

* Install prepackaged plugins locally only (#11656)

* s/uninstall/remove

* Updated ClusterMessage comment

* Updated PluginSync to test against s3 + local storage

model/cluster_message.go

@@ -25,7 +25,10 @@ const (
 	CLUSTER_EVENT_INVALIDATE_CACHE_FOR_ROLES                        = "inv_roles"
 	CLUSTER_EVENT_INVALIDATE_CACHE_FOR_SCHEMES                      = "inv_schemes"
 	CLUSTER_EVENT_CLEAR_SESSION_CACHE_FOR_ALL_USERS                 = "inv_all_user_sessions"
+	CLUSTER_EVENT_INSTALL_PLUGIN                                    = "install_plugin"
+	CLUSTER_EVENT_REMOVE_PLUGIN                                     = "remove_plugin"
 
+	// SendTypes for ClusterMessage.
 	CLUSTER_SEND_BEST_EFFORT = "best_effort"
 	CLUSTER_SEND_RELIABLE    = "reliable"
 )