Fallback on null empty value in ExprBoundaries::try_from_column

[razeghi71]

Which issue does this PR close?

Closes #8262

Rationale for this change

Previously in c9330bc we changed the default empty value for lower and upper bound from ScalarValue::Null to ScalarValue::try_from(field.data_type()). but the drawback of this was that for the types that this wasn't implemented (as mentioned in the issue for Map), this cause the queries to fail. To fix this we can either implement this for other data types (for map I did a prototype in #8488), or fall back on Null which I did in this PR.

What changes are included in this PR?

Explained above.

Are these changes tested?

I tested it using the query provided in the issue.

Are there any user-facing changes?

No

[alamb]

Thanks @razeghi71 -- I think this PR is acceptable to get the queries running, though I think implementing ScalarValue::Map is likely the more robust solution

To merge this PR I think it needs some sort of test (ideally a query in https://github.com/apache/arrow-datafusion/tree/main/datafusion/sqllogictest) that fails without this PR and works with it. This will ensure we don't accidentally break the system again during a future refactor

Thanks again for your help here

[razeghi71]

Since I couldn't find a SQL syntax to create a table containing a map data type, I created it here in code.

[razeghi71]

Thanks @alamb I added a test in explain.slt. Let me know if you think that's enough.

[alamb]

Looks good to me -- thank you @razeghi71

[alamb]

Upon some more thought I think the test might be easier to find in map.slt so I proposed moving it in #8550