blueprint format unit tests

[fgardt]

7c934ca added a little helper for managing BP string unit tests.
The workflow of adding / updating tests should get documented.

List of test BPs:

• test_book (which contains all other BPs)
• fluidboxes:
  • pumps
  • regular_pipes
  • storagetanks
  • valves
• large_connectables:
  • cargo_bays
  • cargo_landing_bays
  • fusion
• artillery
• combinators
• constant_logistic_group
• elevated_rails
• flipped_fluidboxes
• inserters
• long_train
• parametrics
• platform_hub
• quality_chemplants
• rail_test_circle
• train_schedule

Things that could use some tests:

• deconstruction planners
• upgrade planners
• version extractor (with some older BP strings / odd JSON data)
• book nesting (done in feat(blueprint): add more test BPs & fix issues accordingly #228 )
• more circuit control behavior
• ???