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/postgres/000006_create_emojis.up.sql

@@ -0,0 +1,17 @@
+CREATE TABLE IF NOT EXISTS emoji (
+    id VARCHAR(26) PRIMARY KEY,
+    createat bigint,
+    updateat bigint,
+    deleteat bigint,
+    creatorid VARCHAR(26),
+    name VARCHAR(64),
+    UNIQUE(name, deleteat)
+);
+
+CREATE INDEX IF NOT EXISTS idx_emoji_update_at ON emoji (updateat);
+CREATE INDEX IF NOT EXISTS idx_emoji_create_at ON emoji (createat);
+CREATE INDEX IF NOT EXISTS idx_emoji_delete_at ON emoji (deleteat);
+
+DROP INDEX IF EXISTS Name_2;
+
+DROP INDEX IF EXISTS idx_emoji_name;