Remove wrong import in FF AGIPD notebook

A fix for a reported bug at https://in.xfel.eu/redmine/issues/124675#change-463210

As the agipdlib.get_bias_voltage function was removed the code complains when trying to import it.

Description

How Has This Been Tested?

• being tested with the xfel-calibrate CL added by Marcin in the mentioned ticket

Relevant Documents (optional)

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

Reviewers

@schmidtp @roscar @danilevc

notebooks/AGIPD/Characterize_AGIPD_Gain_FlatFields_NBC.ipynb

@@ -90,7 +90,6 @@
     "import numpy as np\n",
     "import sharedmem\n",
     "import XFELDetAna.xfelpyanatools as xana\n",
-    "from cal_tools.agipdlib import get_bias_voltage\n",
     "from cal_tools.agipdutils_ff import (\n",
     "    BadPixelsFF,\n",
     "    any_in,\n",
@@ -125,23 +124,6 @@
     "module = modules[0]"
    ]
   },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "# This is never used in this notebook and should be removed\n",
-    "\n",
-    "# if bias_voltage == 0:\n",
-    "#     # Read the bias voltage from files, if recorded.\n",
-    "#     # If not available, make use of the historical voltage the detector is running at\n",
-    "#     control_filename = f'{raw_folder}/r{run:04d}/RAW-R{run:04d}-{karabo_da_control}-S00000.h5'\n",
-    "#     bias_voltage = get_bias_voltage(control_filename, karabo_id_control)\n",
-    "#     bias_voltage = bias_voltage if bias_voltage is not None else 300\n",
-    "# print(f\"Bias voltage: {bias_voltage}V\")"
-   ]
-  },
   {
    "cell_type": "code",
    "execution_count": null,