Environment variables from `env` can be double quoted

When generating a buildkite pipeline with env config like this:

"env": {
    "ACTION": "symbollint",
    "BUILDKITE_PLUGIN_K8S_INIT_IMAGE": "207762998838.dkr.ecr.us-east-1.amazonaws.com/k8s-buildkite-agent@sha256:c7cbce5a34b77c6f60b16b6f21a51790eee64745a271562956295f16f17231dd",
    "BUILDKITE_PLUGIN_K8S_PRINT_RESULTING_JOB_SPEC": "true",
    "FLAVOR": "QA",
    "K8S_PLUGIN_JOB_CLEANUP_IF_SUCCESSFUL": "false"
},

I end up with a json spec like double quotes my custom env vars:

"env": [
   {
      "name": "ACTION",
      "value": "\"lint-matching-files\""
   },
   {
      "name": "FLAVOR",
      "value": "\"QA\""
   },
   {
      "name": "CI",
      "value": "\"true\""
   },
   {
      "name": "K8S_PLUGIN_JOB_CLEANUP_IF_SUCCESSFUL",
      "value": "\"false\""
   },
   {
      "name": "BUILDKITE",
      "value": "true"
   },
   {

On 5826cbd20a4bd91e602c7a9bba58fd421e45d6c5

EmbarkStudios / k8s-buildkite-plugin

Environment variables from `env` can be double quoted #29