Squashes the following warning:
```
DEBUG: /home/buildbuddy/workspace/output-base/external/rules_jvm_external/private/rules/coursier.bzl:775:18:
Found duplicate artifact versions
com.google.code.gson:gson has multiple versions 2.13.1, 2.10.1
Please remove duplicate artifacts from the artifact list so you do not get unexpected artifact versions
```
This makes it so rules_jvm_external also doesn't package up all the
opencv class files into the final published packages. And is simpler to
maintain.
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
