Adding support of map_top_n_values to Presto

[jainavi17]

Add an UDF for getting top N values of a map, which returns an array of the top N values of map. Optionally a lambda comparator can also be passed to perform a custom comparison of the values. Returns all the value if the value N is greater than or equal to size of the map. N must be >= 0. For N = 0, the function returns empty array.

map_top_n_values(map(K, V), N) -> array(V)

• For N > 0, returns the top N values of a map. If N happens to larger than size of the map, it returns all the values of the map in descending order
• For N = 0, return empty array
• For N < 0, function throws an error.

map_top_n_values(map(K, V), N, function(V, V, int)) -> array(V)
Return the top N values of the map sorted using the lambda comparator.

Test plan - (Please fill in how you tested your changes)
Added unit tests.
Build successfully using the following terminal command

• ./mvnw clean install -Dtest=TestMapTopValuesFunction -fn -pl presto-main
• ./mvnw clean install -Dtest=TestMapTopValuesComparatorFunction -fn -pl presto-main

== RELEASE NOTES ==

General Changes
* Add :func:`map_top_n_values` to return top N values of the provided map. An optional lambda comparator can also be passed as parameter for custom sorting of the values.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: jainavi17 / name: Avinash Jain (be3de6664d30abc21af36be628b9ed16189f76d8)

[kaikalur]

See my comments in the other one - MAP_TOP_N_KEYS - same applies here - just do it as a SQL udf

[jainavi17]

See my comments in the other one - MAP_TOP_N_KEYS - same applies here - just do it as a SQL udf

Cool! Let me do this a SQL UDFs

[jainavi17]

Hi @kaikalur , this PR is similar to #18625 . I've pretty much taken all the feedback from previous PR into consideration. So this should be quick. Let me know

[kaikalur]

Also squash the commits

[highker]

Same comment as the other PR..... The release note is too verbose. We only need one (long) line to explain what it does in English. Also, we need :func: annotation for the function name so it can be linked to the doc you wrote.

[highker]

Please squash the commits

[jainavi17]

Same comment as the other PR..... The release note is too verbose. We only need one (long) line to explain what it does in English. Also, we need :func: annotation for the function name so it can be linked to the doc you wrote.

Done!

[jainavi17]

Can we merge this PR?