Release new lambda/dotnet:8 to address CVE-2024-37371

[jenademoodley]

Hi team,

Checking the latest version of the lambda/dotnet:8 image shows it is using an older version of the krb5-libs package which is vulnerable to CVE-2024-37371:

$ docker run --rm -it --entrypoint '/bin/bash' public.ecr.aws/lambda/dotnet:8 -c 'rpm -qa | grep krb'
krb5-libs-1.21-3.amzn2023.0.4.x86_64

As per ALAS-2024-688, the fix is in package version krb5-libs-1.21.3-1.amzn2023.0.1.x86_64.

Issue also discussed in #171 for the lambda/nodejs:20 image but I see the package was previously updated within the latest image.

Can we update the package in this image as well?