Update scala3-library to 3.3.6

http4s-steward[bot] · http4s-steward[bot] · commit 4ef7668bf1ec · 2025-05-08T12:47:00.000Z
diff --git a/build.sbt b/build.sbt
@@ -1,5 +1,5 @@
 val scala213 = "2.13.12"
-val scala3 = "3.3.1"
+val scala3 = "3.3.6"
 
 name := "http4s-fabric"
 
