libheif_info: Extended the returning results

[bigcat88]

Ref: #154

Changes proposed in this pull request:

• libheif_info now returns additionally encoders and decoders keys

This PR raises minimum libheif version to the 1.15.0

This will allow to get the required decoder_id and pass it to image.load() or something like that in future to use selected decoder/encoder for the operation.

{
       'libheif': '1.15.2',
       'HEIF': 'x265 HEVC encoder (3.4+31-6722fce1f)',
       'AVIF': 'AOMedia Project AV1 Encoder 3.7.0',
       'encoders': {
           'x265': 'x265 HEVC encoder (3.4+31-6722fce1f)',
           'aom': 'AOMedia Project AV1 Encoder v3.7.0',
           'mask': 'mask'
       },
       'decoders': {
           'libde265': 'libde265 HEVC decoder, version 1.0.12',
           'aom': 'AOMedia Project AV1 Decoder v3.7.0'
       }
}

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f17d541) 100.00% compared to head (5edde21) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##            master      #189   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           10        10           
  Lines          906       907    +1     
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+ Hits           906       907    +1     

Files	Coverage Δ
pillow_heif/_lib_info.py	100.00% <100.00%> (ø)
pillow_heif/_version.py	100.00% <100.00%> (ø)
pillow_heif/as_plugin.py	100.00% <100.00%> (ø)
pillow_heif/heif.py	100.00% <100.00%> (ø)