Unable to set Helm values to null in Go

[mrlnstpn]

What happened?

I tried to override the default value of CPU limit using null but it gives me 999m, other test along with this was I tried as well to use the AllowNullValues but it doesn't work as well, it says

    panic: fatal: A precondition has failed for vsrc: value must be valid`

I'm using https://www.pulumi.com/registry/packages/kubernetes/api-docs/helm/v3/release/#kubernetes-helm-sh-v3-release

Example

    resources:
      requests:
        cpu: 10m
        memory: 200Mi
      limits:
        cpu: null
        memory: 200Mi

### Output of `pulumi about`

CLI          
Version      3.134.1
Go Version   go1.23.1
Go Compiler  gc

Plugins
KIND      NAME          VERSION
resource  azure         5.89.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azure-native  2.63.0
resource  azuread       5.53.4
language  go            unknown
resource  kubernetes    3.30.2
resource  rancher2      3.9.0

Host     
OS       ubuntu
Version  22.04
Arch     x86_64

### Additional context

_No response_

### Contributing

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[blampe]

@mrlnstpn can you include the full Helm resource you're using in your program? That will help us reproduce this. The underlying issue is probably tracked in #2997.