Delete groups (legacy communities system) (#8027)

* Remove deprecated feature_communities_v2_prototypes

* Update _components

* i18n

* delint

* Cut out a bit more dead code

* Carve into legacy components

* Carve into mostly the room list code

* Carve into instances of "groupId"

* Carve out more of what comes up with "groups"

* Carve out some settings

* ignore related groups state

* Remove instances of spacesEnabled

* Fix some obvious issues

* Remove now-unused css

* Fix variable naming for legacy components

* Update i18n

* Misc cleanup from manual review

* Update snapshot for changed flag

* Appease linters

* rethemedex

* Remove now-unused AddressPickerDialog

* Make ConfirmUserActionDialog's member a required prop

* Remove useless override from RightPanelStore

* Remove extraneous CSS

* Update i18n

* Demo: "Communities are now Spaces" landing page

* Restore linkify for group IDs

* Demo: Dialog on click for communities->spaces notice

* i18n for demos

* i18n post-merge

* Update copy

* Appease the linter

* Post-merge cleanup

* Re-add spaces_learn_more_url to the new SdkConfig place

* Round 1 of post-merge fixes

* i18n

Co-authored-by: Michael Telatynski <7t3chguy@gmail.com>

res/css/structures/_LeftPanel.scss

@@ -53,9 +53,8 @@ $roomListCollapsedWidth: 68px;
 
 .mx_LeftPanel {
     background-color: $roomlist-bg-color;
-    // TODO decrease this once Spaces launches as it'll no longer need to include the 56px Community Panel
 
-    // Create a row-based flexbox for the GroupFilterPanel and the room list
+    // Create a row-based flexbox for the space panel and the room list
     display: flex;
     contain: content;
     position: relative;
@@ -119,11 +118,6 @@ $roomListCollapsedWidth: 68px;
             display: flex;
             align-items: center;
 
-            .mx_UserMenu {
-                // mini-mode for when Space Panel is disabled
-                margin-right: 12px;
-            }
-
             & + .mx_RoomListHeader {
                 margin-top: 12px;
             }