Add array_to_row helper function

[norberttech]

Currently we only have:

function array_to_rows(array $data, EntryFactory $entryFactory = new NativeEntryFactory(), array|Partitions $partitions = [], ?Schema $schema = null) : Rows

However there are a lot of scenarios where we might want to simply create one row from associative array (not list).

function array_to_rows(array $data, EntryFactory $entryFactory = new NativeEntryFactory(), ?Schema $schema = null) : Rows

Implementation of this function can be literally extracted from array_to_rows

[norberttech]

Resolved by: #1149