Before:
  call ale#assert#SetUpFixerTest('dhall', 'dhall')

After:
  call ale#assert#TearDownFixerTest()

Execute(The default command should be correct):
  AssertFixer
  \ { 'read_temporary_file': 1,
  \   'command': ale#Escape('dhall') . ' format --inplace %t'
  \ }