Fix deployable JARs created by Scala rules.
Fix deployable JARs created by Scala rules.

ianoc/rules_scala,sdtwigg/rules_scala,smparkes/rules_scala,sdtwigg/rules_scala,smparkes/rules_scala,bazelbuild/rules_scala,ianoc/rules_scala,ianoc/rules_scala,bazelbuild/rules_scala,bazelbuild/rules_scala,sdtwigg/rules_scala,smparkes/rules_scala