MySQL 8.0

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create table tbl (
  id int,
  text varchar(100)
);

insert into tbl values
  (1, '</table> 
 
</li>
</ul>'),
  (2, '< /table>   
 
< /li>
< /ul>');

Records: 2  Duplicates: 0  Warnings: 0

select * from tbl;

id
text

1
</table> 
 
</li>
</ul>

2
< /table>   
 
< /li>
< /ul>

select
    REGEXP_REPLACE(
     text
    ,'<[[:blank:][:space:]]*\/table>[[:blank:][:space:]]+<[[:blank:][:space:]]*\/li>[[:blank:][:space:]]+<[[:blank:][:space:]]*\/ul>[[:blank:][:space:]]*'
    ,'</table>'
    ) text
  from tbl;

text

</table>

</table>

update tbl
  set text = REGEXP_REPLACE(
     text
    ,'<[[:blank:][:space:]]*\/table>[[:blank:][:space:]]+<[[:blank:][:space:]]*\/li>[[:blank:][:space:]]+<[[:blank:][:space:]]*\/ul>[[:blank:][:space:]]*'
    ,'</table>'
    )

Rows matched: 2  Changed: 2  Warnings: 0

select * from tbl;

id
text

1
</table>

2
</table>