updates in the DataSources api reference

Author: luisaFelixSalles

src/ansys/dpf/core/data_sources.py

@@ -537,8 +537,8 @@ def result_key(self) -> str:
 
         Returns
         -------
-        str :
-           Result key.
+        str
+            Result key.
 
         Examples
         --------
@@ -562,7 +562,7 @@ def result_files(self):
 
         Returns
         -------
-        list :
+        list
             List of result files.
 
         Examples
@@ -687,7 +687,7 @@ def __str__(self):
 
         Returns
         -------
-        str :
+        str
             Description of the entity.
         """
         from ansys.dpf.core.core import _description