Bump dotnet/sdk from a364676 to 1e8c666 in /.github/docker (#1502)

Bumps dotnet/sdk from `a364676` to `1e8c666`.


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.github/docker/Dockerfile.dotnetrestore

@@ -1,3 +1,3 @@
-FROM mcr.microsoft.com/dotnet/sdk:8.0.401-1-bookworm-slim@sha256:a364676fedc145cf88caad4bfb3cc372aae41e596c54e8a63900a2a1c8e364c6
+FROM mcr.microsoft.com/dotnet/sdk:8.0.401-1-bookworm-slim@sha256:1e8c6666f3e31f96d22a5c77054589f85078a4850595421c6999395f26e79b9a
 
 CMD echo this is a dummy file used to automate dependency upgrades for plugins