Investigate trailing zero truncation issue with sigs.k8s.io/yaml package

[abhay-krishna]

Description

We noticed an issue with the cluster config parsing where if a user wishes to create an EKS-A cluster with a Kubernetes version whose minor version is a multiple of 10, i.e., 1.30, 1.40, etc., the version gets converted into a float64 type when parsed and the trailing zeros gets dropped, thereby leading to downstream methods getting incorrect inputs such as 1.3, 1.4 for the Kubernetes version. This error manifests during cluster creation as

Error: unable to get cluster config from file: kubernetes version 1.3 is not supported by bundles manifest ...

where the Kubernetes version in the output will be the input Kubernetes version without the trailing zeros.

We determined this is caused by bugs (go-yaml/yaml#430, go-yaml/yaml#671) in the underlying gopkg.in/yaml.v2 parser used by the sigs.k8s.io/yaml module (same bug also logged in SIGs YAML) that we consume.

The short-term solution is for the user to always use quotes around their Kubernetes version which prevents it from being parsed as a float64 and instead correctly as a string. However we need to investigate if there is a programmatic way to solve this, possibly by using a different YAML library or making our parsing method aware of this issue and use context-aware logic.

[abhay-krishna]

We have a fix for this in #9185. We circumvent the need for customer to add quotes by adding it in code ourselves after reading in the cluster config file and prior to parsing th contents.