Python: Fix template tests to match updated apply_substitutions signature

Remove stale `cursor=None` kwarg from test calls after the parameter
was removed from TemplateEngine.apply_substitutions in 7ca8044.

Author: knutwannheden

rewrite-python/rewrite/tests/python/template/test_template.py

@@ -93,7 +93,7 @@ def test_replace_placeholder_in_method_args(self):
         assert isinstance(tree, j.MethodInvocation)
 
         result = TemplateEngine.apply_substitutions(
-            tree, {'expr': self._ident("hello")}, cursor=None,
+            tree, {'expr': self._ident("hello")},
         )
 
         assert isinstance(result, j.MethodInvocation)
@@ -111,7 +111,7 @@ def test_replace_placeholder_in_method_select(self):
         assert isinstance(tree, j.MethodInvocation)
 
         result = TemplateEngine.apply_substitutions(
-            tree, {'obj': self._ident("myobj")}, cursor=None,
+            tree, {'obj': self._ident("myobj")},
         )
 
         assert isinstance(result, j.MethodInvocation)
@@ -128,7 +128,7 @@ def test_replace_multiple_placeholders(self):
         assert isinstance(tree, j.Binary)
 
         result = TemplateEngine.apply_substitutions(
-            tree, {'a': self._ident("x"), 'b': self._ident("y")}, cursor=None,
+            tree, {'a': self._ident("x"), 'b': self._ident("y")},
         )
 
         assert isinstance(result, j.Binary)