Bump Newtonsoft.Json from 12.0.3 to 13.0.1 in /RegexDialog

Bumps [Newtonsoft.Json](https://github.com/JamesNK/Newtonsoft.Json) from 12.0.3 to 13.0.1.
- [Release notes](https://github.com/JamesNK/Newtonsoft.Json/releases)
- [Commits](JamesNK/Newtonsoft.Json@12.0.3...13.0.1)

---
updated-dependencies:
- dependency-name: Newtonsoft.Json
  dependency-type: direct:production
...

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

Author: dependabot[bot]

RegexDialog/packages.config

@@ -18,7 +18,7 @@
   <package id="Microsoft.CSharp" version="4.7.0" targetFramework="net47" />
   <package id="Microsoft.Net.Compilers" version="3.8.0" targetFramework="net47" developmentDependency="true" />
   <package id="Microsoft.SDK.Expression.Blend" version="1.0.0" targetFramework="net452" />
-  <package id="Newtonsoft.Json" version="12.0.3" targetFramework="net46" />
+  <package id="Newtonsoft.Json" version="13.0.1" targetFramework="net46" />
   <package id="Ookii.Dialogs" version="3.1.0" targetFramework="net47" />
   <package id="Ookii.Dialogs.WinForms" version="1.2.0" targetFramework="net47" />
   <package id="Ookii.Dialogs.Wpf" version="3.1.0" targetFramework="net47" />