Switch from pretty-simple to pretty-show for native output.

Update tests.

Reason:  it turns out that the native output generated by
pretty-simple isn't always readable by the native reader.
According to https://github.com/cdepillabout/pretty-simple/issues/99
it is not a design goal of the library that the rendered values
be readable using 'read'.  This makes it unsuitable for our
purposes.

pretty-show is a bit slower and it uses 4-space indents
(non-configurable), but it doesn't have this serious drawback.

1 files changed, 24 insertions, 26 deletions

diff --git a/test/command/6836.md b/test/command/6836.md
index 8c89ee0d2..b8e668a62 100644
--- a/test/command/6836.md
+++ b/test/command/6836.md
@@ -9,35 +9,33 @@ See @foo.
 [@buchanan]
 ^D
 [ Para
-  [ Cite
-    [ Citation
-      { citationId = "buchanan"
-      , citationPrefix = []
-      , citationSuffix = []
-      , citationMode = NormalCitation
-      , citationNoteNum = 1
-      , citationHash = 0
-      }
+    [ Cite
+        [ Citation
+            { citationId = "buchanan"
+            , citationPrefix = []
+            , citationSuffix = []
+            , citationMode = NormalCitation
+            , citationNoteNum = 1
+            , citationHash = 0
+            }
+        ]
+        [ Str "[@buchanan]" ]
     ]
-    [ Str "[@buchanan]" ]
-  ]
-, OrderedList
-  ( 1, Example, TwoParens ) [ [] ]
+, OrderedList ( 1 , Example , TwoParens ) [ [] ]
+, Para [ Str "See" , Space , Str "1." ]
 , Para
-  [ Str "See", Space, Str "1." ]
-, Para
-  [ Cite
-    [ Citation
-      { citationId = "buchanan"
-      , citationPrefix = []
-      , citationSuffix = []
-      , citationMode = NormalCitation
-      , citationNoteNum = 2
-      , citationHash = 0
-      }
+    [ Cite
+        [ Citation
+            { citationId = "buchanan"
+            , citationPrefix = []
+            , citationSuffix = []
+            , citationMode = NormalCitation
+            , citationNoteNum = 2
+            , citationHash = 0
+            }
+        ]
+        [ Str "[@buchanan]" ]
     ]
-    [ Str "[@buchanan]" ]
-  ]
 ]
 ```