Restore default target output path on Windows CI builds

[jvff]

Motivation

When Tokio was upgraded (#2994), the CI Windows builds started failing due to insufficient disk space. As a temporary workaround, the target output directory was changed to use a separate larger drive (C: instead of D:). However, it would be best to not have this workaround, and to just optimize the Zebra build to use less disk space.

Related Work

#2994 introduced the workaround.

[mpguerra]

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[teor2345]

Let's do this after we've resolved most of our duplicate dependencies.
If we do it too soon, the build directory could get big again, and we might have to revert it.

[dconnolly]

Not strictly required for release candidate