Update scala-compiler, scala-library, ... to 2.13.15

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       matrix:
         java-version: [ 8 ]
-        scala: [ '2.11.12', '2.12.19', '2.13.13' ]
+        scala: [ '2.11.12', '2.12.19', '2.13.15' ]
     steps:
       - name: Checkout
         uses: actions/checkout@v3
@@ -33,7 +33,7 @@ jobs:
     strategy:
       matrix:
         java-version: [ 8 ]
-        scala: [ '2.11.12', '2.12.19', '2.13.13' ]
+        scala: [ '2.11.12', '2.12.19', '2.13.15' ]
     steps:
       - name: Checkout
         uses: actions/checkout@v3

build.sbt

@@ -32,7 +32,7 @@ inThisBuild(
 
 lazy val scala212 = "2.12.19"
 lazy val scala211 = "2.11.12"
-lazy val scala213 = "2.13.13"
+lazy val scala213 = "2.13.15"
 
 lazy val scalatestVersion = "3.2.19"
 lazy val h2               = "2.3.230"