Add "packaging" dependency to pyproject.toml

There has been a runtime dependency on packaging since commit ef8e7fd.

Also remove unused import from packaging.

Author: dhmjhu

pyproject.toml

@@ -17,6 +17,7 @@ classifiers = [
 
 dependencies = [
     "numpy",
+    "packaging",
 ]
 
 [project.urls]

src/probeinterface/io.py

@@ -17,7 +17,7 @@
 import warnings
 import json
 from collections import OrderedDict
-from packaging.version import Version, parse
+from packaging.version import parse
 import numpy as np
 from xml.etree import ElementTree