KCL 0.12 converts the string "yes" into yes when outputting yaml, which breaks yaml 1.1 parsers like Kubernetes

[cypres]

Bug Report

Yaml 1.2 no longer recognize yes as a boolean, but Yaml 1.1 does, which includes Kubernetes. Meaning if you use KCL 0.12 with Kubernetes and set a string "yes" it becomes a boolean instead, causing type errors such as:

Deployment: json: cannot unmarshal bool into Go struct field EnvVar.spec.template.spec.containers.env.value of type string

This would be fairly common in the EnvVar's for a ContainerSpec, where a user is likely to set an environment variable to a string "yes", which KCL now handles incorrectly.

This is a regression from KCL 0.11.4

1. Minimal reproduce step (Required)

import manifests

schema Foo:
    a: str

foo = Foo {
    a: "yes"
}

manifests.yaml_stream([foo])

2. What did you expect to see? (Required)

a: 'yes'

3. What did you see instead (Required)

a: yes

4. What is your KCL components version? (Required)

KCL 0.12

[cypres]

Okay, I can see #2012 fixes this problem.