Bump mixin-deep from 1.3.1 to 1.3.2 in /demo

Bumps [mixin-deep](https://github.com/jonschlinkert/mixin-deep) from 1.3.1 to 1.3.2.
- [Release notes](https://github.com/jonschlinkert/mixin-deep/releases)
- [Commits](jonschlinkert/mixin-deep@1.3.1...1.3.2)

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

Author: dependabot[bot]

demo/yarn.lock

@@ -6232,9 +6232,9 @@ mississippi@^3.0.0:
     through2 "^2.0.0"
 
 mixin-deep@^1.2.0:
-  version "1.3.1"
-  resolved "https://registry.yarnpkg.com/mixin-deep/-/mixin-deep-1.3.1.tgz#a49e7268dce1a0d9698e45326c5626df3543d0fe"
-  integrity sha512-8ZItLHeEgaqEvd5lYBXfm4EZSFCX29Jb9K+lAHhDKzReKBQKj3R+7NOF6tjqYi9t4oI8VUfaWITJQm86wnXGNQ==
+  version "1.3.2"
+  resolved "https://registry.yarnpkg.com/mixin-deep/-/mixin-deep-1.3.2.tgz#1120b43dc359a785dce65b55b82e257ccf479566"
+  integrity sha512-WRoDn//mXBiJ1H40rqa3vH0toePwSsGb45iInWlTySa+Uu4k3tYUSxa2v1KqAiLtvlrSzaExqS1gtk96A9zvEA==
   dependencies:
     for-in "^1.0.2"
     is-extendable "^1.0.1"