added test for C++ Backend for cocktail shaker sort

Author: arvinder004

pydatastructs/linear_data_structures/_backend/cpp/algorithms/algorithms.cpp

@@ -5,7 +5,7 @@
 
 static PyMethodDef algorithms_PyMethodDef[] = {
     {"cocktail_shaker_sort", (PyCFunction) cocktail_shaker_sort,
-        METH_VARARGS | METH_KEYWORDS, ""},
+    METH_VARARGS | METH_KEYWORDS, ""},
     {"quick_sort", (PyCFunction) quick_sort,
      METH_VARARGS | METH_KEYWORDS, ""},
     {"bubble_sort", (PyCFunction) bubble_sort,