ParallelListComp leads to syntactically invalid result

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This Haskell file compiles just fine with ghc 8.10.

{-# LANGUAGE ParallelListComp #-}

         main = undefined
         b = undefined
         c = undefined
         d = undefined
         e = undefined

         a      =  [ b
                            |  c
                            | d <- e
                           ]

But running brittany 0.13.1.1 on it causes it to print an error: ERROR: brittany pretty printer returned syntactically invalid result.
Running with --output-on-errors produces this output

{-# LANGUAGE ParallelListComp #-}

main = undefined
b = undefined
c = undefined
d = undefined
e = undefined

a = [ b | c d <- e ]

brittany.yaml

conf_debug:
  dconf_roundtrip_exactprint_only: false
  dconf_dump_bridoc_simpl_par: false
  dconf_dump_ast_unknown: false
  dconf_dump_bridoc_simpl_floating: false
  dconf_dump_config: false
  dconf_dump_bridoc_raw: false
  dconf_dump_bridoc_final: false
  dconf_dump_bridoc_simpl_alt: false
  dconf_dump_bridoc_simpl_indent: false
  dconf_dump_annotations: false
  dconf_dump_bridoc_simpl_columns: false
  dconf_dump_ast_full: false
conf_forward:
  options_ghc:
  - -XBangPatterns
  - -XBlockArguments
  - -XExplicitForAll
  - -XExplicitNamespaces
  - -XGADTs
  - -XImplicitParams
  - -XLambdaCase
  - -XMultiWayIf
  - -XNumericUnderscores
  - -XParallelListComp
  - -XPatternGuards
  - -XQuasiQuotes
  - -XRecursiveDo
  - -XTemplateHaskell
  - -XTupleSections
  - -XTypeApplications
  - -XViewPatterns
conf_errorHandling:
  econf_ExactPrintFallback: ExactPrintFallbackModeInline
  econf_Werror: false
  econf_omit_output_valid_check: false
  econf_produceOutputOnErrors: false
conf_preprocessor:
  ppconf_CPPMode: CPPModeAbort
  ppconf_hackAroundIncludes: false
conf_version: 1
conf_layout:
  lconfig_altChooser:
    tag: AltChooserBoundedSearch
    contents: 3
  lconfig_importColumn: 50
  lconfig_alignmentLimit: 30
  lconfig_indentListSpecial: true
  lconfig_indentAmount: 2
  lconfig_alignmentBreakOnMultiline: true
  lconfig_cols: 80
  lconfig_indentPolicy: IndentPolicyFree
  lconfig_indentWhereSpecial: true
  lconfig_columnAlignMode:
    tag: ColumnAlignModeMajority
    contents: 0.7

Start by running brittany 0.13.1.1 on the supplied Haskell example with ParallelListComp enabled, then compile both the input and formatted output with GHC. Trace the formatter path for parallel list comprehensions; done means the formatted result remains syntactically valid and preserves the parallel comprehension structure.

Written by the indexing model from the issue text.

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