Update api_client.nustache

modules/openapi-generator/src/main/resources/powershell/api_client.mustache

@@ -36,6 +36,7 @@ function Invoke-{{{apiNamePrefix}}}ApiClient {
 
     $Configuration = Get-{{{apiNamePrefix}}}Configuration
     $RequestUri = $Configuration["BaseUrl"] + $Uri
+    $DefaultHeaders = $Configuration["DefaultHeaders"]
     # should make sure that SkipCertificateCheck is not set for PowerShell 5
     $SkipCertificateCheck = $Configuration["SkipCertificateCheck"]
     $Proxy = $Configuration["Proxy"]
@@ -59,7 +60,7 @@ function Invoke-{{{apiNamePrefix}}}ApiClient {
     }
 
     # Content-Type and multipart handling
-    $ContentType= SelectHeaders -Headers $ContentTypes
+    $ContentType = SelectHeaders -Headers $ContentTypes
     if ($ContentType) {
         $HeaderParameters['Content-Type'] = $ContentType
         if ($ContentType -eq 'multipart/form-data') {
@@ -68,7 +69,7 @@ function Invoke-{{{apiNamePrefix}}}ApiClient {
     }
 
     # add default headers if any
-    foreach ($header in $Configuration["DefaultHeaders"].GetEnumerator()) {
+    foreach ($header in $DefaultHeaders.GetEnumerator()) {
         $HeaderParameters[$header.Name] = $header.Value
     }