Replace go-migrate with morph (#19116)

db/migrations/postgres/000010_create_group_channels.up.sql

@@ -0,0 +1,15 @@
+CREATE TABLE IF NOT EXISTS groupchannels (
+    groupid VARCHAR(26),
+    autoadd boolean,
+    schemeadmin boolean,
+    createat bigint,
+    deleteat bigint,
+    updateat bigint,
+    channelid VARCHAR(26),
+    PRIMARY KEY(groupid, channelid)
+);
+
+ALTER TABLE groupchannels ADD COLUMN IF NOT EXISTS schemeadmin boolean;
+
+CREATE INDEX IF NOT EXISTS idx_groupteams_schemeadmin ON groupchannels (schemeadmin);
+CREATE INDEX IF NOT EXISTS idx_groupchannels_channelid ON groupchannels (channelid);