build: update Python SDK Version to 1.21.0b3 (#1569)

* Update Python SDK Version to 1.21.0b3

* Update pyproject.toml

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Co-authored-by: AzureFunctionsPython <funcdisc@microsoft.com>

pyproject.toml

@@ -26,7 +26,7 @@ classifiers = [
     "Intended Audience :: Developers"
 ]
 dependencies = [
-     "azure-functions==1.21.0b2",
+     "azure-functions==1.21.0b3",
      "python-dateutil ~=2.9.0",
      "protobuf~=3.19.3; python_version == '3.7'",
      "protobuf~=4.25.3; python_version >= '3.8'",