Update prerelease iteration

Update for preview.2.

Author: martincostello

eng/Versions.props

@@ -7,7 +7,7 @@
     <VersionPrefix>$(MajorVersion).$(MinorVersion).$(PatchVersion)</VersionPrefix>
     <PackageValidationBaselineVersion Condition=" '$(EnablePackageValidation)' == 'true' AND '$(PackageValidationBaselineVersion)' == '' ">9.0.0</PackageValidationBaselineVersion>
     <PreReleaseVersionLabel>preview</PreReleaseVersionLabel>
-    <PreReleaseVersionIteration>1</PreReleaseVersionIteration>
+    <PreReleaseVersionIteration>2</PreReleaseVersionIteration>
     <PreReleaseBrandingLabel>Preview $(PreReleaseVersionIteration)</PreReleaseBrandingLabel>
     <StabilizePackageVersion Condition="'$(StabilizePackageVersion)' == ''">false</StabilizePackageVersion>
     <DotNetFinalVersionKind Condition="'$(StabilizePackageVersion)' == 'true'">release</DotNetFinalVersionKind>