fix spurious indent and newlines in rendering of nkRecList (#23121)

Rendering of `nkRecList` produces an indent and adds a new line at the
end. However for things like case object `of`/`else` branches or `when`
branches this is already done, so this produces 2 indents and an extra
new line. Instead, just add an indent in the place where the indent that
`nkRecList` produces is needed, for the rendering of the final node of
`nkObjectTy`. There doesn't seem to be a need to add the newline.

Before:

```nim
case x*: bool
of true:
    y*: int

of false:
  nil
```

After:

```nim
case x*: bool
of true:
  y*: int
of false:
  nil
```

1 files changed, 1 insertions, 2 deletions

diff --git a/nimdoc/extlinks/project/expected/main.html b/nimdoc/extlinks/project/expected/main.html
index 1a58ea2ac..f46d72115 100644
--- a/nimdoc/extlinks/project/expected/main.html
+++ b/nimdoc/extlinks/project/expected/main.html
@@ -95,8 +95,7 @@
   <h1><a class="toc-backref" href="#7">Types</a></h1>
   <dl class="item">
     <div id="A">
-  <dt><pre><a href="main.html#A"><span class="Identifier">A</span></a> <span class="Other">=</span> <span class="Keyword">object</span>
-  </pre></dt>
+  <dt><pre><a href="main.html#A"><span class="Identifier">A</span></a> <span class="Other">=</span> <span class="Keyword">object</span></pre></dt>
   <dd>