[Security] Bump mixin-deep from 1.3.0 to 1.3.1

Bumps [mixin-deep](https://github.com/jonschlinkert/mixin-deep) from 1.3.0 to 1.3.1. **This update includes security fixes.**
- [Release notes](https://github.com/jonschlinkert/mixin-deep/releases)
- [Commits](jonschlinkert/mixin-deep@1.3.0...1.3.1)

Signed-off-by: dependabot[bot] <support@dependabot.com>

yarn.lock

@@ -3280,8 +3280,8 @@ mississippi@^1.3.0:
     through2 "^2.0.0"
 
 mixin-deep@^1.2.0:
-  version "1.3.0"
-  resolved "https://registry.yarnpkg.com/mixin-deep/-/mixin-deep-1.3.0.tgz#47a8732ba97799457c8c1eca28f95132d7e8150a"
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/mixin-deep/-/mixin-deep-1.3.1.tgz#a49e7268dce1a0d9698e45326c5626df3543d0fe"
   dependencies:
     for-in "^1.0.2"
     is-extendable "^1.0.1"