style: remove trailing whitespace

Removed all trailing whitespace.

src/jcloud_docsgen/utils.py

@@ -70,7 +70,7 @@ class ExistingFile(pathlib.Path):
 def _quote(string: str, quotation_mark: str) -> str:
     '''
     Quotes a string.
-    
+
     :param string: The string to quote
     :type string: str
     :param quotation_mark: The quotation mark
@@ -98,7 +98,7 @@ def human_readable_list(
     :type final_separator: str
     :param quotation_mark: The characters that are inserted before and
                            after an element. Default is ''.
-    
+
     :return: The human-readable list.
     :rtype: str
     '''
@@ -106,11 +106,11 @@ def human_readable_list(
     # empty list
     if not ls:
         return ''
-    
+
     # list with one element
     if len(ls) == 1:
         return _quote(str(ls[0]), quotation_mark)
-    
+
     return ', '.join(
         [
             _quote(
@@ -165,7 +165,7 @@ def assert_that_is_instance(
                 obj
             ).__name__}\''
         )
-    
+
 def non_empty_str(value: Union[str, None]) -> Union[str, None]:
     '''
     Returns the value or ``None``.
@@ -184,7 +184,7 @@ def non_empty_str(value: Union[str, None]) -> Union[str, None]:
 
     if value is None:
         return None
-    
+
     if value.strip() == '':
         return None