[Change Request] Invoke-PnPGraphMethod -AdditionalHeaders does not accept a hashtable

Reporting an Issue or Missing Feature

I'm considering this an issue (not a feature request) since I'd expect others to also file this as a bug. I'm all for using generics for type safety, but...come on. I shouldn't have to cast a whole new dictionary on a separate line just to use this argument.

Expected behavior

The -AdditionalHeaders argument of Invoke-PnPGraphMethod should accept a hashtable the sake of simplicity and readability.

Actual behavior

When using a hashtable in the -AdditionalHeaders argument of Invoke-PnPGraphMethod, I receive the error message:

Cannot bind parameter 'AdditionalHeaders'. Cannot convert the "System.Collections.Hashtable" value of type "System.Collections.Hashtable" to type "System.Collections.Generic.IDictionary`2[System.String,System.String]".

The workaround is:

$dict = [System.Collections.Generic.Dictionary[string,string]]::new()
$dict.Add('header','value')
$dict.Add('header2','value2')
Invoke-PnPGraphMethod ... -AdditionalHeaders $dict

Steps to reproduce behavior

Sample command (Connected to PnP with -Interactive or an app registration with User.Read.All):

Invoke-PnPGraphMethod -Method Get -Url 'https://graph.microsoft.com/v1.0/users?$select=displayName&$filter=assignedLicenses/$count ne 0&$count=true' -AdditionalHeaders @{ ConsistencyLevel = 'eventual' }

What is the version of the Cmdlet module you are running?

2.4.0

Which operating system/environment are you running PnP PowerShell on?

[x] Windows
[ ] Linux
[ ] MacOS
[ ] Azure Cloud Shell
[ ] Azure Functions
[ ] Other : please specify

pnp / powershell