Update to later NB.GV and SemVer 2

Ix.NET/Source/Directory.build.props

@@ -26,11 +26,11 @@
   <Target Name="GetPackagingOutputs" />
   
   <PropertyGroup>
-    <NerdbankGitVersioningVersion>2.0.4-beta</NerdbankGitVersioningVersion>
+    <NerdbankGitVersioningVersion>2.0.21-beta</NerdbankGitVersioningVersion>
   </PropertyGroup>
   
   <ItemGroup>
-    <PackageReference Include="Nerdbank.GitVersioning" Version="2.0.4-beta" PrivateAssets="all" />
+    <PackageReference Include="Nerdbank.GitVersioning" Version="2.0.21-beta" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- https://github.com/NuGet/Home/issues/4337 -->

Ix.NET/Source/version.json

@@ -5,6 +5,9 @@
     "^refs/heads/develop$", // we release out of develop
     "^refs/tags/v\\d+\\.\\d+" // we also release tags starting with vN.N
   ],
+  "nugetPackageVersion":{
+    "semVer": 2
+  },
   "cloudBuild": {
     "buildNumber": {
       "enabled": true

Rx.NET/Source/Directory.build.props

@@ -30,11 +30,11 @@
   <Target Name="GetPackagingOutputs" />
   
   <PropertyGroup>
-    <NerdbankGitVersioningVersion>2.0.4-beta</NerdbankGitVersioningVersion>
+    <NerdbankGitVersioningVersion>2.0.21-beta</NerdbankGitVersioningVersion>
   </PropertyGroup>
   
   <ItemGroup>
-    <PackageReference Include="Nerdbank.GitVersioning" Version="2.0.4-beta" PrivateAssets="all" />
+    <PackageReference Include="Nerdbank.GitVersioning" Version="2.0.21-beta" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- https://github.com/NuGet/Home/issues/4337 -->

Rx.NET/Source/version.json

@@ -5,6 +5,9 @@
     "^refs/heads/develop$", // we release out of develop
     "^refs/tags/v\\d+\\.\\d+" // we also release tags starting with vN.N
   ],
+  "nugetPackageVersion":{
+    "semVer": 2
+  },
   "cloudBuild": {
     "buildNumber": {
       "enabled": true