Fix a typo that stop CWAgent release test from working

[XinRanZhAWS]

Issue description:
Fix a typo that stop CWAgent release test from working

Noted that in current config,

aws-application-signals-test-framework/sample-apps/dotnet/dotnet-ec2-win-main-setup.ps1

Line 25 in 7599169

msiexec /i amazon-cloudwatch-agent.msi

Test script require that the CWA to be named to amazon-cloudwatcih-agent.msi for the script to run, the staging image grab by s3 from test repo is NOT match this naming method, thus CWA is not running in the first place, result in the test not working

Test
https://github.com/aws-observability/aws-application-signals-test-framework/actions/runs/15052116489/job/42309601468

Description of changes:
rename S3 download target name for CWAgent release test to match normal cases
Rollback procedure:
revert
<Can we safely revert this commit if needed? If not, detail what must be done to safely revert and why it is needed.>

Ensure you've run the following tests on your changes and include the link below:

To do so, create a test.yml file with name: Test and workflow description to test your changes, then remove the file for your PR. Link your test run in your PR description. This process is a short term solution while we work on creating a staging environment for testing.

NOTE: TESTS RUNNING ON A SINGLE EKS CLUSTER CANNOT BE RUN IN PARALLEL. See the needs keyword to run tests in succession.

• Run Java EKS on e2e-playground in us-east-1 and eu-central-2
• Run Python EKS on e2e-playground in us-east-1 and eu-central-2
• Run metric limiter on EKS cluster e2e-playground in us-east-1 and eu-central-2
• Run EC2 tests in all regions
• Run K8s on a separate K8s cluster (check IAD test account for master node endpoints; these will change as we create and destroy clusters for OS patching)

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