MV_MAX


Converts a multivalued field into a single valued field containing the maximum value. For example:
```esql
ROW a=[3, 5, 1]
| EVAL max_a = MV_MAX(a)
```

It can be used by any field type, including keyword fields. In that case picks the
last string, comparing their utf-8 representation byte by byte:
```esql
ROW a=["foo", "zoo", "bar"]
| EVAL max_a = MV_MAX(a)
```

Supported types:
