Bump System.Text.RegularExpressions

Bumps System.Text.RegularExpressions from 4.3.0 to 4.3.1.

---
updated-dependencies:
- dependency-name: System.Text.RegularExpressions
  dependency-type: direct:production
...

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Author: dependabot[bot]

TreeViewEventToCommandDemo/TreeViewEventToCommandDemo/packages.config

@@ -40,7 +40,7 @@
   <package id="System.Security.Cryptography.X509Certificates" version="4.3.0" targetFramework="net46" />
   <package id="System.Text.Encoding" version="4.3.0" targetFramework="net46" />
   <package id="System.Text.Encoding.Extensions" version="4.3.0" targetFramework="net46" />
-  <package id="System.Text.RegularExpressions" version="4.3.0" targetFramework="net46" />
+  <package id="System.Text.RegularExpressions" version="4.3.1" targetFramework="net46" />
   <package id="System.Threading" version="4.3.0" targetFramework="net46" />
   <package id="System.Threading.Tasks" version="4.3.0" targetFramework="net46" />
   <package id="System.Threading.Timer" version="4.3.0" targetFramework="net46" />