Add explanation for added fields using bullet list

Author: hefniraera

docs/user_manual/processing_algs/qgis/checkgeometry.rst

@@ -585,9 +585,17 @@ Outputs
    * - **Holes errors**
      - ``ERRORS``
      - [vector: point]
-     - Output point layer representing the error locations and information
-       (the ID and name of the input layer, the geometry part,
-       ring and vertex index of the erroneous feature, x and y coordinates of the error).
+     - Output point layer representing the error locations and information.
+       Other than the input attributes, the output layer also contains the following fields:
+       
+       - ``gc_layerid``: the ID of the input layer.
+       - ``gc_layername``: the name of the input layer.
+       - ``gc_partidx``: the index of the feature's geometry part containing the hole.
+       - ``gc_ringidx``: the index of the feature's geometry ring containing the hole.
+       - ``gc_vertidx``
+       - ``gc_errorx``: the x coordinate of the centroid of the hole.
+       - ``gc_errory``: the y coordinate of the centroid of the hole.
+       - ``gc_error``
    * - **Polygon with holes**
      - ``OUTPUT``
      - [vector: polygon]