Fix xargs: command line cannot be assembled, too long

[yesid-lopez]

Hello there!

I was getting this issue whenever I wanted to update the values with the make command:

$ make                                                                           
rm -rf manifests
./scripts/build.sh main.jsonnet /Users/yelopez/go/bin/jsonnet
using jsonnet from arg
+ set -o pipefail
+ rm -rf manifests
+ mkdir -p manifests/setup
+ /Users/yelopez/go/bin/jsonnet -J vendor -m manifests main.jsonnet
+ xargs '-I{}' sh -c 'cat {} | $(go env GOPATH)/bin/gojsontoyaml > {}.yaml; rm -f {}' -- '{}'
xargs: command line cannot be assembled, too long
make: *** [manifests] Error 1

Sending a PR that solved the issue for me.