Fix warnings found by the Undefined Behavior Sanitizer #530
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Fixes runtime error warnings found when running the tests with the undefined behavior sanitizer enabled.
Update callback functions to use correct signature, see aws_simple_completion_callback.
Since the CI-build is not using
-fno-sanitize-recover=allthe warnings are recoverable and will not fail the CI build.The warnings are also found when a user incorporates
aws-sdk-cppinto a project and build it using an UB sanitizer.By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.