[Avro] Decoder flush panics for map whose value field contains metadata

[yongkyunlee]

Describe the bug

Decoder flush panics when the value field of a map type contains metadata (e.g. enum type)

To Reproduce

When we generate avro data with a map field whose value type is enum, the decoder panics at flush with an error like below

thread 'reader::record::tests::test_map_entries_with_enum_value' panicked at arrow-array/src/array/map_array.rs:132:64:
called `Result::unwrap()` on an `Err` value: InvalidArgumentError("MapArray expected data type Struct(key Utf8, value Dictionary(Int32, Utf8)) got Struct(key Utf8, value Dictionary(Int32, Utf8)) for \"entries\"")

Expected behavior

Flush should be successful with any valid value field type of a map.

Additional context

[jecsand838]

@yongkyunlee I hate to do this to you again, but #8220 already has the updates needed to handle this as well.

[jecsand838]

@yongkyunlee @alamb This issue should be resolved now with #8220 merged.

[alamb]

Thanks again @yongkyunlee and @jecsand838

FWIW saying that someone's bug is already fixed is not a bad thing ;)