Update sbt, scripted-plugin to 1.12.8 in series/0.23

http4s-steward[bot] · http4s-steward[bot] · commit 538751da2b01 · 2026-03-24T20:42:41.000Z
diff --git a/project/build.properties b/project/build.properties
@@ -1 +1 @@
-sbt.version=1.12.7
+sbt.version=1.12.8
