Disable the authorizer callback when reparsing the schema. This avoids

undesirable authorization failures following an ALTER TABLE.

FossilOrigin-Name: 805d01cdabb48a69eb986a7f084e53eb25d76b7f

src/auth.c

@@ -111,6 +111,7 @@ int sqlite3AuthReadCol(
   char *zDb = db->aDb[iDb].zName; /* Name of attached database */
   int rc;                         /* Auth callback return code */
 
+  if( db->init.busy ) return SQLITE_OK;
   rc = db->xAuth(db->pAuthArg, SQLITE_READ, zTab,zCol,zDb,pParse->zAuthContext
 #ifdef SQLITE_USER_AUTHENTICATION
                  ,db->auth.zAuthUser