[backend][assetmodel] Add defaultFormat method

This method simplify the code to retrive the format
to put as default value when, for example, creating
a new input or output for an algorithm as well as
values for tests.
4 jobs for 246_fix_dataformat_list_for_protocol_templates in 11 minutes and 51 seconds
Status Name Job ID Coverage
  Build
passed build_linux_36 #205911
docker

00:11:44

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passed build_linux_37 #205912
docker

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passed build_macosx_36 #205909
macosx

00:10:32

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passed build_macosx_37 #205910
macosx

00:10:08

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