OOMScoreAdj is incorrectly cleared even if no plugin performs an adjustment

[samuelkarp]

From kubernetes/kubernetes#128251, and see the new failing unit test in #116.

[mikebrow]

@klihub FYI

[samuelkarp]

Leaving this open to track the remainder of the work:

• new tag for github.com/containerd/nri: https://github.com/containerd/nri/releases/tag/v0.7.0
• update containerd to consume the new version: deps: bump github.com/containerd/nri containerd#10884