test: add alter column case for stb

tests/script/tsim/stable/add_column.sim

+system sh/stop_dnodes.sh
+system sh/deploy.sh -n dnode1 -i 1
+system sh/exec.sh -n dnode1 -s start
+sql connect
+
+print ========== prepare stb and ctb
+sql create database db vgroups 1
+sql create table db.stb (ts timestamp, c1 int, c2 binary(4)) tags(t1 int, t2 float, t3 binary(16)) comment "abd"
+sql create table db.ctb using db.stb tags(1, 2, "3")
+sql insert into db.ctb values(now, 1, "2")
+
+sql show db.stables
+if $rows != 1 then
+  return -1
+endi
+if $data[0][0] != stb then
+  return -1
+endi
+if $data[0][1] != db then
+  return -1
+endi
+if $data[0][3] != 3 then
+  return -1
+endi
+if $data[0][4] != 3 then
+  return -1
+endi
+if $data[0][6] != abd then
+  return -1
+endi
+
+sql show db.tables
+if $rows != 1 then
+  return -1
+endi
+if $data[0][0] != ctb then
+  return -1
+endi
+if $data[0][1] != db then
+  return -1
+endi
+if $data[0][3] != 3 then
+  return -1
+endi
+if $data[0][4] != stb then
+  return -1
+endi
+if $data[0][6] != 2 then
+  return -1
+endi
+if $data[0][9] != CHILD_TABLE then
+  return -1
+endi
+
+sql select * from db.stb
+if $rows != 1 then
+  return -1
+endi
+if $data[0][1] != 1 then
+  return -1
+endi
+if $data[0][2] != 2 then
+  return -1
+endi
+if $data[0][3] != 1 then
+  return -1
+endi
+
+print ========== add column
+sql alter table db.stb add column c3 int
+sql alter table db.stb add column c4 bigint
+sql alter table db.stb add column c5 binary(12)
+
+sql show db.stables
+if $data[0][3] != 6 then
+  return -1
+endi
+
+sql show db.tables
+if $data[0][3] != 6 then
+  return -1
+endi
+
+sql select * from db.stb
+print $data[0][0] $data[0][1] $data[0][2] $data[0][3] $data[0][4] $data[0][5] $data[0][6]
+if $rows != 1 then
+  return -1
+endi
+if $data[0][1] != 1 then
+  return -1
+endi
+if $data[0][2] != 2 then
+  return -1
+endi
+if $data[0][3] != NULL then
+  return -1
+endi
+if $data[0][4] != NULL then
+  return -1
+endi
+if $data[0][5] != NULL then
+  return -1
+endi
+if $data[0][6] != 1 then
+  return -1
+endi
+