Update version: 1.65.0 -> 1.66.0

Features:

- Update to more modern target frameworks. See #2561 for details.

Src/Support/CommonProjectProperties.xml

@@ -2,7 +2,7 @@
 
   <!-- common nupkg information -->
   <PropertyGroup>
-    <Version>1.65.0</Version>
+    <Version>1.66.0</Version>
     <Authors>Google LLC</Authors>
     <Copyright>Copyright 2021 Google LLC</Copyright>
     <PackageTags>Google</PackageTags>

features.json

@@ -1,8 +1,8 @@
 {	
   "language": "csharp",	
   "description": "C# libraries for Google APIs.",	
-  "releaseVersion": "1.65.0", "comment1": "Version of generated package.",	
-  "currentSupportVersion": "1.65.0", "comment2": "Version of support library upon which to depend.",	
+  "releaseVersion": "1.66.0", "comment1": "Version of generated package.",	
+  "currentSupportVersion": "1.66.0", "comment2": "Version of support library upon which to depend.",	
 
   "clouds_comment": "Defines the map of Google.Cloud packages that supercede Google.Apis packages",	
   "cloudPackageMap": {