Bump github.com/gorilla/mux from 1.8.0 to 1.8.1

Bumps [github.com/gorilla/mux](https://github.com/gorilla/mux) from 1.8.0 to 1.8.1.
- [Release notes](https://github.com/gorilla/mux/releases)
- [Commits](gorilla/mux@v1.8.0...v1.8.1)

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

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

Author: dependabot[bot]

go.mod

@@ -4,7 +4,7 @@ go 1.17
 
 require (
 	github.com/eclipse/paho.mqtt.golang v1.4.3
-	github.com/gorilla/mux v1.8.0
+	github.com/gorilla/mux v1.8.1
 )
 
 require (

go.sum

@@ -1,7 +1,7 @@
 github.com/eclipse/paho.mqtt.golang v1.4.3 h1:2kwcUGn8seMUfWndX0hGbvH8r7crgcJguQNCyp70xik=
 github.com/eclipse/paho.mqtt.golang v1.4.3/go.mod h1:CSYvoAlsMkhYOXh/oKyxa8EcBci6dVkLCbo5tTC1RIE=
-github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
-github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
+github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
+github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=