remove nsamples hack

this follows from HERA-Team/hera_pspec#407

notebooks/single_baseline_postprocessing_and_pspec.ipynb

@@ -905,10 +905,7 @@
     "            if flags is not None:\n",
     "                flags[ap + (pstokes,)] = combined_flags\n",
     "            if nsamples is not None:\n",
-    "                nsamples[ap + (pstokes,)] = combined_nsamples * 4.0\n",
-    "                # TODO: This 4.0 is very ad hoc and is put here to fix an issue with error bars that arose in the \n",
-    "                # change of pol_convention from \"avg\" to \"sum\". Once we've tracked down all the appropriate factors\n",
-    "                # of 2, this should not be necessary. See https://github.com/HERA-Team/hera_pspec/issues/406 for details."
+    "                nsamples[ap + (pstokes,)] = combined_nsamples"
    ]
   },
   {