fix: add .psm1 extension to manifest RootModule

Author: bravo-kernel

Templates/Dotnet/ModuleBuilderModule/dotnet-post-action.ps1

@@ -6,7 +6,7 @@ Set-StrictMode -Version Latest
 
 # generate manifest
 $manifestPath = "./Source/{moduleName}.psd1"
-New-ModuleManifest -RootModule "{moduleName}" -Path $manifestPath -ModuleVersion 0.0.1
+New-ModuleManifest -RootModule "{moduleName}.psm1" -Path $manifestPath -ModuleVersion 0.0.1
 
 # convert manifest to UTF-8 without BOM
 $content = Get-Content $manifestPath