Warnings (and maybe errors) are reported in unstable order

[Mingun]

This can be demonstrated by test encoding_str_warnings which is failed with the following message:

[info] - encoding_str_warnings *** FAILED ***
[info]   encoding_str_warnings.ksy: /seq/1/encoding:
[info]   	warning: use canonical encoding name `UTF-8` instead of `utF-8` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /seq/2/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `latin1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /instances/alias/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `ISo8859-1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /instances/wrong_case/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `iSo-8859-1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]    did not equal encoding_str_warnings.ksy: /seq/1/encoding:
[info]   	warning: use canonical encoding name `UTF-8` instead of `utF-8` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /seq/2/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `latin1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /instances/wrong_case/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `iSo-8859-1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name)
[info]   
[info]   encoding_str_warnings.ksy: /instances/alias/encoding:
[info]   	warning: use canonical encoding name `ISO-8859-1` instead of `ISo8859-1` (see https://doc.kaitai.io/ksy_style_guide.html#encoding-name) (SimpleMatchers.scala:34)

The reason because /instances/wrong_case and /instances/alias instances reported in different order in expected message and by the compiler.

flatMap here traverses maps in order that the map provides, and default Map implementation is unordered.

[Mingun]

Actually, that is test that wrong, because all properties with fields was changed to SortedMap in kaitai-io/kaitai_struct_compiler@5f561e1