Added support for async read of Avro

[jorgecarleitao]

This PR adds support to read Avro asynchronously via AsyncRead + AsyncSeek. As usual, the IO is separated from CPU/blocking code so that we can perform run async / non-blocking code separated from blocking code.

This also adds an example showing how to read an Avro file with Tokio runtime, as well as an entry to the guide about it.

[codecov]

Codecov Report

Merging #620 (8bfc2d5) into main (a8c55f9) will increase coverage by 0.15%.
The diff coverage is 87.87%.

@@            Coverage Diff             @@
##             main     #620      +/-   ##
==========================================
+ Coverage   69.59%   69.74%   +0.15%     
==========================================
  Files         301      303       +2     
  Lines       16779    16818      +39     
==========================================
+ Hits        11677    11730      +53     
+ Misses       5102     5088      -14     

Impacted Files	Coverage Δ
src/io/avro/read/deserialize.rs	72.64% <ø> (ø)
src/io/avro/read/schema.rs	52.38% <0.00%> (ø)
src/io/avro/read_async/block.rs	82.75% <82.75%> (ø)
src/io/avro/read_async/utils.rs	85.71% <85.71%> (ø)
src/io/avro/read_async/metadata.rs	95.00% <95.00%> (ø)
src/io/avro/read/block.rs	71.42% <100.00%> (+0.84%)	⬆️
src/io/avro/read/decompress.rs	80.64% <100.00%> (ø)
src/io/avro/read/mod.rs	81.25% <100.00%> (ø)
src/bitmap/utils/slice_iterator.rs	92.53% <0.00%> (+1.49%)	⬆️
src/error.rs	36.36% <0.00%> (+9.09%)	⬆️

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