Refine comments on fast-path for integer itemsize

Clarified comments regarding fast-path application for integer widths.

Author: divya1974

pandas/core/algorithms.py

@@ -578,7 +578,7 @@ def f(c, v):
             and comps_array.dtype.kind in "iu"
             # Only apply fast-path for 64-bit integer widths to avoid
             # surprising behaviour on platforms or dtypes with different
-            # itemsize (see GH discussions). Narrowing to 8-byte ints
+            # itemsize. Narrowing to 8-byte ints
             # keeps the fast-path safe and performant for the common case.
             and values.dtype.itemsize == 8
             and comps_array.dtype.itemsize == 8