update docker files

[GarrettBeatty]

update integ test docker files to use dotnet10 base image.

remove libicu since they include it and make it self contained false since dotnet runtime is already installed.

ran one integ test to confirm it still works

 Image pushed: 147997163238.dkr.ecr.us-east-1.amazonaws.com/durable-integ-multi-b6265606:latest
 Creating Lambda function: durable-integ-multi-aec665fe
 Waiting for function to become Active... (ARN: arn:aws:lambda:us-east-1:147997163238:function:durable-integ-multi-aec665fe)
 Response: {"Status":"completed","Data":"a-chain-b-c-d-e"}
 [FindArn] Starting search for execution name 'integ-test-0c3dca09ad4141c4afa494456efedb00' on function 'durable-integ-multi-aec665fe' (timeout: 60s)
 [FindArn] attempt 1: List returned 1 executions
 [FindArn]   - name='integ-test-0c3dca09ad4141c4afa494456efedb00' status=RUNNING arn=arn:aws:lambda:us-east-1:147997163238:function:durable-integ-multi-aec665fe:$LATEST/durable-execution/integ-test-0c3dca09ad4141c4afa494456efedb00/5641f410-9bdc-38ce-8f9a-9a46a461cf68
 [FindArn] matched on attempt 1
 [WaitForHistory] attempt 1: 13 events [ExecutionStarted:1,ExecutionSucceeded:1,InvocationCompleted:1,StepStarted:5,StepSucceeded:5]
 [WaitForHistory] event dump (13 total):
   [0] type=ExecutionStarted name=integ-test-0c3dca09ad4141c4afa494456efedb00 ts=2026-06-11T20:11:28.1289999Z
   [1] type=StepStarted name=step_1 ts=2026-06-11T20:11:32.4260001Z
   [2] type=StepSucceeded name=step_1 ts=2026-06-11T20:11:32.7109999Z
   [3] type=StepStarted name=step_2 ts=2026-06-11T20:11:32.7599999Z
   [4] type=StepSucceeded name=step_2 ts=2026-06-11T20:11:32.7960000Z
   [5] type=StepStarted name=step_3 ts=2026-06-11T20:11:32.8480000Z
   [6] type=StepSucceeded name=step_3 ts=2026-06-11T20:11:32.8789999Z
   [7] type=StepStarted name=step_4 ts=2026-06-11T20:11:32.9519999Z
   [8] type=StepSucceeded name=step_4 ts=2026-06-11T20:11:32.9939999Z
   [9] type=StepStarted name=step_5 ts=2026-06-11T20:11:33.0650000Z
   [10] type=StepSucceeded name=step_5 ts=2026-06-11T20:11:33.1110000Z
   [11] type=InvocationCompleted name=<null> ts=2026-06-11T20:11:33.3729999Z
   [12] type=ExecutionSucceeded name=integ-test-0c3dca09ad4141c4afa494456efedb00 ts=2026-06-11T20:11:33.3729999Z
 Deleting function: durable-integ-multi-aec665fe
 Deleting ECR repository: durable-integ-multi-b6265606



Test Run Successful.
Total tests: 1
     Passed: 1
 Total time: 1.0239 Minutes
  Amazon.Lambda.DurableExecution.IntegrationTests test net10.0 succeeded (61.9s)

Test summary: total: 1, failed: 0, succeeded: 1, skipped: 0, duration: 61.8s
Build succeeded in 66.9s

[GarrettBeatty]

still need custom entry point so that it uses our executable entry point