Use online checksums for PowerShell in .NET SDK Dockerfiles

[lbussell]

This is part of #6548. Instead of using hard-coded checksums, they should be downloaded from the build/release storage account. This makes the Dockerfiles more flexible and simplifies this repo's maintenance, since we will no longer need to calculate or keep track of checksums.

For a given PowerShell release, checksums are available at: https://powershellinfraartifacts-gkhedzdeaghdezhr.z01.azurefd.net/tool/$powershell_version/SHA512SUMS. For example: https://powershellinfraartifacts-gkhedzdeaghdezhr.z01.azurefd.net/tool/7.4.11/SHA512SUMS

Example:

dotnet-docker/src/runtime/10.0/alpine3.22/amd64/Dockerfile

Lines 7 to 16 in 157267f

	RUN dotnet_version=10.0.0-preview.6.25358.103 \
	&& wget \
	https://builds.dotnet.microsoft.com/dotnet/Runtime/$dotnet_version/dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz \
	https://builds.dotnet.microsoft.com/dotnet/Runtime/$dotnet_version/dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz.sha512 \
	&& sha512sum -c dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz.sha512 \
	&& mkdir --parents /dotnet \
	&& tar --gzip --extract --no-same-owner --file dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz --directory /dotnet \
	&& rm \
	dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz \
	dotnet-runtime-$dotnet_version-linux-musl-x64.tar.gz.sha512

[lbussell]

@adityapatwardhan, @SeeminglyScience, is this file OK to use for this purpose? I found it by looking through PowerShell's publishing code. Is it stable and is the PowerShell team committed to continuing to publish it for future releases?

[adityapatwardhan]

@lbussell yes, this is the correct file to use for checksums