##### SUMMARY
mysql_db module should be able to create/drop multiple databases

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
lib/ansible/modules/database/mysql/mysql_db.py

##### ADDITIONAL INFORMATION
Why and what it would solve:
Avoids repetitive tasks to create/delete more than one databases (similar to https://github.com/ansible/ansible/issues/56059)

<!--- Paste example playbooks or commands between quotes below -->

- Create (Multiple databases)
```yaml
  tasks:
  - name: Create multiple databases (provided in comma separated form)
    mysql_db:
      name: bobdata, bobthebuilder
      state: present
  - name: Create multiple databases (provided in list form)
    mysql_db:
      name:
        - bobdata
        - bobthebuilder
      state: present
```

- Delete/Drop (Multiple databases)
```yaml
  - name: Delete/drop multiple databases (provided in comma separated form)
    mysql_db:
      name: bobdata, bobthebuilder
      state: absent
  - name: Delete/drop multiple databases (provided in list form)
    mysql_db:
      name:
        - bobdata
        - bobthebuilder
      state: absent
```

Credits for the idea to @Andersson007 from comment https://github.com/ansible/ansible/pull/56721#issuecomment-505128646
if not os.path.exists(target):
        return module.fail_json(msg="target %s does not exist on the host" % target)
    cmd = [module.get_bin_path('mysql', True)]
    
    if config_file:
        cmd.append("--defaults-extra-file=%s" % shlex_quote(config_file))
    if user:
        cmd.append("--user=%s" % shlex_quote(user))
    if password:
        cmd.append("--password=%s" % shlex_quote(password))
    if ssl_cert is not None:
        cmd.append("--ssl-cert=%s" % shlex_quote(ssl_cert))
    if ssl_key is not None:
        cmd.append("--ssl-key=%s" % shlex_quote(ssl_key))
    if ssl_ca is not None:
        cmd.append("--ssl-ca=%s" % shlex_quote(ssl_ca))
    if socket is not None:
        cmd.append("--socket=%s" % shlex_quote(socket))
    else:
        cmd.append("--host=%s" % shlex_quote(host))
        cmd.append("--port=%i" % port)
    if not all_databases:
        cmd.append("-D")
        cmd.append(shlex_quote(''.join(db_name)))
    comp_prog_path = None
    if os.path.splitext(target)[-1] == '.gz':
        comp_prog_path = module.get_bin_path('gzip', required=True)
    elif os.path.splitext(target)[-1] == '.bz2':
        comp_prog_path = module.get_bin_path('bzip2', required=True)