)

The RuntimeSupport integration tests now run in parallel, and each test
class provisions its own IAM role (GetRole/CreateRole/AttachRolePolicy at
startup, ListAttachedRolePolicies/DetachRolePolicy/DeleteRole at teardown).
The IAM control-plane APIs have low request-rate limits, so the parallel
burst intermittently throttles with 'Rate exceeded', failing
TestAllNET10HandlersAsync and TestThreadingLogging in setup rather than on
any assertion.

Wrap the IAM calls in a throttle-aware retry with exponential backoff so
the parallel startup/teardown burst is smoothed instead of failing.

The RuntimeSupport integration test fixture copies the entire repo root
into a temp directory (in CicdRelease mode) so dotnet lambda package can
resolve the test apps' ProjectReferences. The recursive copy indiscriminately
grabbed bin/ and obj/ build outputs. When the integration test projects run
in parallel, a concurrent build or Roslyn loading an analyzer (e.g. the newly
added Amazon.Lambda.DurableExecution.Analyzers) holds those files open,
causing File.CopyTo to throw 'being used by another process' and failing all
24 tests during fixture initialization.

Skip bin/obj (alongside the existing .vs skip) — dotnet lambda package
regenerates them anyway, so excluding them removes the lock contention and
speeds up the copy.