Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/channels/db/migrations/mysql/000099_create_drafts.up.sql

@@ -0,0 +1,12 @@
+CREATE TABLE IF NOT EXISTS Drafts (
+    CreateAt bigint(20) DEFAULT NULL,
+    UpdateAt bigint(20) DEFAULT NULL,
+    DeleteAt bigint(20) DEFAULT NULL,
+    UserId varchar(26) NOT NULL,
+    ChannelId varchar(26) NOT NULL,
+    RootId varchar(26) DEFAULT '',
+    Message text,
+    Props text,
+    FileIds text,
+    PRIMARY KEY (UserId, ChannelId, RootId)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;