Bump azure-core (#3299)

Author: dependabot[bot]

packages/autorest.python/test/vanilla/version-tolerant/requirements.txt

@@ -5,7 +5,7 @@ pytest-cov
 pytest-asyncio==0.14.0;python_full_version>="3.5.2"
 async_generator;python_full_version>="3.5.2"
 isodate==0.6.1
-azure-core==1.37.0
+azure-core==1.38.0
 -e ./Expected/AcceptanceTests/AdditionalPropertiesVersionTolerant
 -e ./Expected/AcceptanceTests/AnythingVersionTolerant
 -e ./Expected/AcceptanceTests/BodyArrayVersionTolerant