Refactor CHEF cookbooks - ruby

Question

I have a CHEF recipe for package install on windows hosts. We used to use chef13 client; however we have upgraded to chef16, and we are getting some issues with the cookbook migration.
When I run the existing role as-it-is on a win2k16 chef16 kitchen platform, I get this error,
Chef::Exceptions::ImmutableAttributeModification
------------------------------------------------
Node attributes are read-only when you do not specify which precedence level to set. To set an attribute use code like `node.default["key"] = "value"'
and it points out to this section of the recipe
67: guid = guid.gsub(/{/, '').gsub(/}/, '') # remove {}
68: log "[#{role}][#{recipe_name}][#{app_name}]: GUID for installer #{app_name} is #{guid}"
69>> app_params.store('product_guid', guid) # add GUID to the list of parameters
70: end
Hence, what I understand that chef16 dosen't like the hash.store method.
I have tried some other alternate solutions to update the hash, however they do not work.
Using merge method:-
app_params.merge!({ :product_guid => 'guid' })
Using precedence level explicitly:- ( I have used .default, .override as well, however its the same symptom)
node.force_override!['app_params']['product_guid'] = guid
(reff from : https://github.com/chef/chef/issues/6563)
Note that when using the above methods, i do not get any failures, however the hash dosent get updated at all.
I have added few log statements to show this:-
log "[#{role}][#{recipe_name}][#{app_name}]: app_params.keys is #{app_params.keys}"
log "[#{role}][#{recipe_name}][#{app_name}]: app_params is #{JSON.pretty_generate(app_params)}"
* log[[my-role][my-recipe][my-pkgName]: app_params.keys is ["app_name", "full_path", "action"]] action write
* log[[my-role][my-recipe][my-pkgName]: app_params is {
"app_name": "my-pkgName",
"full_path": "https://myArtifactRepo/.../.../../my-pkgName.msi",
"action": "install"
}] action write
## ^^ hash keys and hash values (app_params.keys and app_params) BEFORE the force_override method is used
log "[#{role}][#{recipe_name}][#{app_name}]: app_params.keys is #{app_params.keys}"
log "[#{role}][#{recipe_name}][#{app_name}]: app_params is #{JSON.pretty_generate(app_params)}"
* log[[my-role][my-recipe][my-pkgName]: app_params.keys is ["app_name", "full_path", "action"]] action write
* log[[my-role][my-recipe][my-pkgName]: app_params is {
"app_name": "my-pkgName",
"full_path": "https://myArtifactRepo/.../.../../my-pkgName.msi",
"action": "install"
}] action write
## ^^ hash keys and hash values (app_params.keys and app_params) AFTER the force_override method is used
Note that the hash and hash key values has not been updated it is still,
["app_name", "full_path", "action"];
however we would expect
["app_name", "full_path", "action", "product_guid"]
and the hash itself like,
"app_name": "my-pkgName",
"full_path": "https://myArtifactRepo/.../.../../my-pkgName.msi",
"action": "install",
"product_guid" : XXXXYYY-0WRR-1234-ABCD-3ERDFR234GRT