Bump github.com/gorilla/mux from 1.7.3 to 1.8.1

Bumps [github.com/gorilla/mux](https://github.com/gorilla/mux) from 1.7.3 to 1.8.1.
- [Release notes](https://github.com/gorilla/mux/releases)
- [Commits](gorilla/mux@v1.7.3...v1.8.1)

---
updated-dependencies:
- dependency-name: github.com/gorilla/mux
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/Shopify/toxiproxy v2.1.4+incompatible
 	github.com/go-playground/locales v0.12.1 // indirect
 	github.com/go-playground/universal-translator v0.16.0
-	github.com/gorilla/mux v1.7.3
+	github.com/gorilla/mux v1.8.1
 	github.com/gorilla/websocket v1.4.1
 	github.com/kr/pretty v0.1.0 // indirect
 	github.com/leodido/go-urn v1.1.0 // indirect

go.sum

@@ -7,8 +7,8 @@ github.com/go-playground/locales v0.12.1 h1:2FITxuFt/xuCNP1Acdhv62OzaCiviiE4kotf
 github.com/go-playground/locales v0.12.1/go.mod h1:IUMDtCfWo/w/mtMfIE/IG2K+Ey3ygWanZIBtBW0W2TM=
 github.com/go-playground/universal-translator v0.16.0 h1:X++omBR/4cE2MNg91AoC3rmGrCjJ8eAeUP/K/EKx4DM=
 github.com/go-playground/universal-translator v0.16.0/go.mod h1:1AnU7NaIRDWWzGEKwgtJRd2xk99HeFyHw3yid4rvQIY=
-github.com/gorilla/mux v1.7.3 h1:gnP5JzjVOuiZD07fKKToCAOjS0yOpj/qPETTXCCS6hw=
-github.com/gorilla/mux v1.7.3/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
+github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
+github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=