Exec plugin not working for provider/v3

[AndriySidliarskiy]

Hello, the exec plugin is not working properly for v3 of the provider.

Link for documentation example https://registry.terraform.io/providers/hashicorp/helm/latest/docs#exec-plugins:~:text=Exec%20plugins-,Some,-cloud%20providers%20have

│ Error: Missing key/value separator
│
│ on providers.tf line 41, in provider "helm":
│ 38: kubernetes = {
│ 39: host = module.eks.cluster_endpoint
│ 40: cluster_ca_certificate = base64decode(module.eks.cluster_certificate_authority_data)
│ 41: exec {
│
│ Expected an equals sign ("=") to mark the beginning of the attribute value.