Tests.yml: develop NDTensors explicitly on TestsITensors

`[workspace] projects` was added in Pkg 1.12; on Julia 1.10 (LTS),
Pkg silently ignores the [workspace] table and resolves NDTensors
from the registry instead of in-tree. That makes the lts CI legs
test against stale registry NDTensors, masked only because the
in-tree version currently matches the latest registered version.

`extra-dev-paths: "NDTensors"` runs `Pkg.develop(path="NDTensors")`
on the active project before buildpkg, forcing in-tree NDTensors
regardless of Pkg version. Idempotent on 1.12+ where workspace
already resolves it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mtfishman

.github/workflows/Tests.yml

@@ -38,6 +38,7 @@ jobs:
       os: "${{ matrix.os }}"
       nthreads: 2
       test-args: "base"
+      extra-dev-paths: "NDTensors"
       localregistry: "https://github.com/ITensor/ITensorRegistry.git"
     secrets:
       CODECOV_TOKEN: "${{ secrets.CODECOV_TOKEN }}"