build(deps-dev): update rake-compiler-dock requirement from = 1.3.0 t…

…o 1.3.1

Updates the requirements on [rake-compiler-dock](https://github.com/rake-compiler/rake-compiler-dock) to permit the latest version.
- [Release notes](https://github.com/rake-compiler/rake-compiler-dock/releases)
- [Changelog](https://github.com/rake-compiler/rake-compiler-dock/blob/master/History.md)
- [Commits](rake-compiler/rake-compiler-dock@1.3.0...1.3.1)

---
updated-dependencies:
- dependency-name: rake-compiler-dock
  dependency-type: direct:development
...

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

Gemfile

@@ -11,7 +11,7 @@ group :development do
 
   # building extensions
   gem "rake-compiler", "1.2.5"
-  gem "rake-compiler-dock", "= 1.3.0"
+  gem "rake-compiler-dock", "1.3.1"
 
   # documentation
   gem "hoe-markdown", "= 1.4.0"