Remove BuildBarn setup from @graknlabs_dependencies (#142)

As we've decided to no longer proceed with BuildBarn, there's no point in keeping the code in the repo

Author: vmax

.gitignore

@@ -5,5 +5,3 @@ bazel-bin
 bazel-out
 bazel-dependencies
 bazel-testlogs
-.terraform
-*.tfstate*