Update scala-library to 2.13.6 (#453)

Co-authored-by: kenji yoshida <6b656e6a69@gmail.com>

Author: scala-steward

.travis.yml

@@ -7,7 +7,7 @@ language: scala
 scala:
   - 2.11.12
   - 2.12.13
-  - 2.13.5
+  - 2.13.6
   - 3.0.0-RC3
   - 3.0.0
 

build.sbt

@@ -55,7 +55,7 @@ lazy val junit = libraryDependencies += "com.novocode" % "junit-interface" % "0.
 
 lazy val scala211 = "2.11.12"
 lazy val scala212 = "2.12.13"
-lazy val scala213 = "2.13.5"
+lazy val scala213 = "2.13.6"
 lazy val scala30  = "3.0.0"
 
 lazy val compat = MultiScalaCrossProject(JSPlatform, JVMPlatform, NativePlatform)(