deps: remove upper bound on packaging dependency

Towards #1435

Author: tswast

setup.py

@@ -40,7 +40,7 @@
     # https://github.com/googleapis/google-cloud-python/issues/10566
     "google-cloud-core >= 1.4.1, <3.0.0dev",
     "google-resumable-media >= 0.6.0, < 3.0dev",
-    "packaging >= 14.3, <22.0.0dev",
+    "packaging >= 14.3",
     "protobuf>=3.19.5,<5.0.0dev,!=3.20.0,!=3.20.1,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",  # For the legacy proto-based types.
     "python-dateutil >= 2.7.2, <3.0dev",
     "requests >= 2.21.0, < 3.0.0dev",