Bump JetBrains.Annotations from 2019.1.1 to 2019.1.3

Bumps JetBrains.Annotations from 2019.1.1 to 2019.1.3.

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

src/Directory.Build.props

@@ -15,7 +15,7 @@
  </PropertyGroup>
  <PropertyGroup>
     <PackageVersion_LibGit2Sharp>0.26.0</PackageVersion_LibGit2Sharp>    
-    <PackageVersion_JetBrainsAnnotations>2019.1.1</PackageVersion_JetBrainsAnnotations>
+    <PackageVersion_JetBrainsAnnotations>2019.1.3</PackageVersion_JetBrainsAnnotations>
     <PackageVersion_YamlDotNet>6.1.1</PackageVersion_YamlDotNet>
  </PropertyGroup>
 </Project>