message: Add extra assertion in Table::remove_column
diff: @@ -401,6 +401,9 @@ void Table::remove_column(ColKey col_key)
  if (col_key == m_primary_key_col) {
  do_set_primary_key_column(ColKey());
  }
  + else {
  + REALM_ASSERT_RELEASE(m_primary_key_col.get_index().val != col_key.get_index().val);
  + }
  bump_content_version();
  bump_storage_version();
  erase_root_column(col_key); // Throws
  