tar in 2.9.1 results in invalid headers

[mattem]

We have a number of manual loads of container images via tars in tests. The upgrade diff to bazel-lib 2.9.1 (and 2.9.0) results in an error loading these tars into Docker with the error:

archive/tar: invalid tar header

No other error is given. This happens on different Linux flavours.

Potential culprit, 3b6a3d5

[alexeagle]

Another libarchive release is coming from BCR, we'll have to experiment to see if this is still reproducible.