Embed sdk versions (#68)

Part of https://github.com/pulumi/ci-mgmt/issues/915

Install pulumi in standard way 

Use the same method as other providers to install the pulumi CLI.
- Lock the version of the CLI and therefore codegen for consistent build
results.
- Ensure the local language plugins are using by disabling ambient
plugins.

Enable respect schema version

Remove setting version at SDK build time

---------

Co-authored-by: Bryce Lampe <bryce@pulumi.com>

sdk/dotnet/Pulumi.DockerBuild.csproj

@@ -9,6 +9,7 @@
     <PackageProjectUrl>https://pulumi.com</PackageProjectUrl>
     <RepositoryUrl>https://github.com/pulumi/pulumi-docker-build</RepositoryUrl>
     <PackageIcon>logo.png</PackageIcon>
+    <Version>1.0.0-alpha.0+dev</Version>
 
     <TargetFramework>net6.0</TargetFramework>
     <Nullable>enable</Nullable>