alejandra modifies the logical contents of multiline strings

[srhb]

given the file:

# trailing-space-in-multiline-string.nix
''
  foo 
''

(note the trailing space character, foo )

alejandra reformats it:

# trailing-space-in-multiline-string.nix
''
  foo
''

... that is, it deletes the trailing space.

alejandra cannot know that this is safe for a given multiline string and shouldn't modify the actual contents.