message: Formatting improvements in tests
diff: >> Yes:
  >> Target := term
  (stratified.record_intro
  - [ ( "data", stratified.array_intro
  + [ ( "data",
  + stratified.array_intro
  [ stratified.record_intro []
  , stratified.record_intro []
  - ])
  + ]
  + )
  , ( "len", stratified.int_intro 2 )
  ]).
  