fix: don't break doc builds / fix imaginary config sample formatting

Signed-off-by: Josh <josh.t.richards@gmail.com>

config/config.sample.php

@@ -1302,19 +1302,19 @@
 /**
  * custom path for ffmpeg binary
  *
- * Defaults to ``null`` and falls back to searching ``avconv`` and ``ffmpeg`` in the configured ``PATH`` environment
+ * Defaults to ``null`` and falls back to searching ``avconv`` and ``ffmpeg`` 
+ * in the configured ``PATH`` environment
  */
 'preview_ffmpeg_path' => '/usr/bin/ffmpeg',
 
 /**
  * Set the URL of the Imaginary service to send image previews to.
- * Also requires the
- *  - ``OC\Preview\Imaginary``
- * provider to be enabled in the 'enabledPreviewProviders' array, to create previews for these mimetypes:
- * bmp, x-bitmap, png, jpeg, gif, heic, heif, svg+xml, tiff, webp and illustrator.
- * If you want Imaginary to also create preview images from PDF Documents, you have to add
- *  - ``OC\Preview\ImaginaryPDF``
- * provider as well.
+ * Also requires the ``OC\Preview\Imaginary`` provider to be enabled in the 
+ * ``enabledPreviewProviders`` array, to create previews for these mimetypes: bmp, 
+ * x-bitmap, png, jpeg, gif, heic, heif, svg+xml, tiff, webp and illustrator.
+ *
+ * If you want Imaginary to also create preview images from PDF Documents, you 
+ * have to add the ``OC\Preview\ImaginaryPDF`` provider as well.
  *
  * See https://github.com/h2non/imaginary
  */