Update dependencies from https://github.com/dotnet/iot build 20190607.2 (#488)

- Iot.Device.Bindings - 0.1.0-prerelease.19307.2
- System.Device.Gpio - 0.1.0-prerelease.19307.2

eng/Version.Details.xml

 <?xml version="1.0" encoding="utf-8"?>
 <Dependencies>
   <ProductDependencies>
-    <Dependency Name="System.Device.Gpio" Version="0.1.0-prerelease.19306.3">
+    <Dependency Name="System.Device.Gpio" Version="0.1.0-prerelease.19307.2">
       <Uri>https://github.com/dotnet/iot</Uri>
-      <Sha>8f0a4a533867417844e72d045d66c1eb0e734ebc</Sha>
+      <Sha>c1813befb4e00d18040c592827d401b750eeb8d9</Sha>
     </Dependency>
-    <Dependency Name="Iot.Device.Bindings" Version="0.1.0-prerelease.19306.3">
+    <Dependency Name="Iot.Device.Bindings" Version="0.1.0-prerelease.19307.2">
       <Uri>https://github.com/dotnet/iot</Uri>
-      <Sha>8f0a4a533867417844e72d045d66c1eb0e734ebc</Sha>
+      <Sha>c1813befb4e00d18040c592827d401b750eeb8d9</Sha>
     </Dependency>
   </ProductDependencies>
   <ToolsetDependencies>

eng/Versions.props

@@ -3,9 +3,8 @@
   <PropertyGroup>
     <PreReleaseVersionLabel>prerelease</PreReleaseVersionLabel>
     <!-- dotnet/iot dependencies -->
-    <SystemDeviceGpioPackageVersion>0.1.0-prerelease.19306.3</SystemDeviceGpioPackageVersion>
-    <IotDeviceBindingsPackageVersion>0.1.0-prerelease.19306.3</IotDeviceBindingsPackageVersion>
-
+    <SystemDeviceGpioPackageVersion>0.1.0-prerelease.19307.2</SystemDeviceGpioPackageVersion>
+    <IotDeviceBindingsPackageVersion>0.1.0-prerelease.19307.2</IotDeviceBindingsPackageVersion>
     <!-- dotnet/arcade dependencies -->
     <MicrosoftDotNetGenAPIPackageVersion>1.0.0-beta.19306.12</MicrosoftDotNetGenAPIPackageVersion>
   </PropertyGroup>