Update cats-core to 2.6.0

Author: 47erbot

github4s/src/test/scala/github4s/utils/TestData.scala

@@ -114,7 +114,7 @@ trait TestData {
 
   val encoding = Some("utf-8")
 
-  val validRefSingle   = "heads/master"
+  val validRefSingle   = "heads/main"
   val validRefMultiple = "heads/feature"
   val invalidRef       = "heads/feature-branch-that-no-longer-exists"
 

project/ProjectPlugin.scala

@@ -15,7 +15,7 @@ object ProjectPlugin extends AutoPlugin {
 
     lazy val V = new {
       val base64: String    = "0.3.0"
-      val cats: String      = "2.5.0"
+      val cats: String      = "2.6.0"
       val circe: String     = "0.13.0"
       val http4s: String    = "0.21.22"
       val paradise: String  = "2.1.1"