Possible .dockerignore misconfiguration

Hello, and thank you for your work on this repository!

As part of my research, I am analyzing how developers configure .dockerignore in popular repositories.

During my analysis, I noticed that `/.dockerignore` might have been written under the assumption that .dockerignore and .gitignore follow the same pattern semantics, while they actually differ.[^1] In particular, the following pattern drew my attention:

https://github.com/aws/aws-xray-daemon/blob/e3869dd20637810a69612f0cfdf1588187b3b388/.dockerignore#L10

According to Docker's specification, this pattern matches `.DS_Store` only in the top-level directory. (To ignore `.DS_Store` in any directory, the .dockerignore file needs to list `**/.DS_Store`)

Was this pattern written intentionally? If not, I'd be happy to submit a pull request to adjust it.

And if possible, could you tell me whether you were aware of the difference between .dockerignore and .gitignore? (I would like to know whether the differences are generally well recognized, or if they tend to slip developers' minds.)

Thank you again for maintaining this repository!

[^1]: See [.gitignore doc](https://git-scm.com/docs/gitignore), [.dockerignore doc](https://docs.docker.com/build/concepts/context/#dockerignore-files), and [a blog post about the differences](https://zzz.buzz/2018/05/23/differences-of-rules-between-gitignore-and-dockerignore/)

Start by reading /.dockerignore at the referenced commit and Docker's .dockerignore pattern documentation. Confirm whether the listed .DS_Store pattern is intended to cover nested paths; done means resolving the intent and, if needed, updating the pattern and validating the resulting diff.

Written by the indexing model from the issue text.