remove msrest dependency from mgmt template + add isodate (Azure#29318)

* remove msrest dependency + add isodate

* Update setup.py

---------

Co-authored-by: Yuchao Yan <[email protected]>

Author: swathipil

tools/azure-sdk-tools/packaging_tools/templates/packaging_files/setup.py

@@ -71,7 +71,7 @@
         'pytyped': ['py.typed'],
     },
     install_requires=[
-        "msrest>=0.7.1",
+        "isodate<1.0.0,>=0.6.1",
         {%- if need_msrestazure %}
         "msrestazure>=0.4.32,<2.0.0",
         {%- endif %}