removes unnecessary column

schema/comments_ddl.sql

@@ -28,7 +28,6 @@ ALTER TABLE COMMENT ADD COLUMN SigningTs TEXT DEFAULT NULL;
 CREATE TABLE IF NOT EXISTS CHANNEL(
     ClaimId     TEXT    NOT NULL,
     Name        TEXT    NOT NULL,
-    PublicKey   TEXT    NOT NULL,
     CONSTRAINT CHANNEL_PK PRIMARY KEY (ClaimId)
         ON CONFLICT IGNORE
 );