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, 26 insertions, 28 deletions

diff --git a/test/command/3779.md b/test/command/3779.md
index 45c91a92c..04111c2a6 100644
--- a/test/command/3779.md
+++ b/test/command/3779.md
@@ -21,39 +21,37 @@
 }
 ^D
 [ BulletList
-  [
-    [ Para
-      [ Str "Pandoc"
-      , Space
-      , Str "is"
-      , Space
-      , Str "100%"
-      , Space
-      , Str "awesome."
+    [ [ Para
+          [ Str "Pandoc"
+          , Space
+          , Str "is"
+          , Space
+          , Str "100%"
+          , Space
+          , Str "awesome."
+          ]
       ]
     ]
-  ]
 , BulletList
-  [
-    [ Para
-      [ Str "Pandoc"
-      , Space
-      , Str "is"
-      , Space
-      , Str "200%"
-      , Space
-      , Str "awesome."
+    [ [ Para
+          [ Str "Pandoc"
+          , Space
+          , Str "is"
+          , Space
+          , Str "200%"
+          , Space
+          , Str "awesome."
+          ]
       ]
     ]
-  ]
 , Para
-  [ Str "Pandoc"
-  , Space
-  , Str "is"
-  , Space
-  , Str "300%"
-  , Space
-  , Str "awesome."
-  ]
+    [ Str "Pandoc"
+    , Space
+    , Str "is"
+    , Space
+    , Str "300%"
+    , Space
+    , Str "awesome."
+    ]
 ]
 ```