feat: Convert a Map of Structs to Array with Entries()

[uurl]

Description

This PR fixes #5452 Convert a Map of Structs to Array with Entries()

Testing done

java io.confluent.ksql.function.udf.array.EntriesTest

Reviewer checklist

• [ ] Ensure docs are updated if necessary. (eg. if a user visible feature is being added or changed).
• [ ] Ensure relevant issues are linked (description should include text like "Fixes #")

[ghost]

@confluentinc It looks like @uurl just signed our Contributor License Agreement. :+1:

Always at your service,

clabot

[spena]

Thanks @uurl

It looks good, but I missed a test we need to add. It's in ksqldb-functional-tests/src/test/resources/query-validation-tests/array.json It has a test for queries sorted that uses ENTRIES in all supported types. Could you add one for the map of structs?

[spena]

@uurl Jenkins is failing, could you rebase your branch from master?

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