Update logback monorepo to v1.5.15 (#317)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -1,5 +1,5 @@
 [versions]
-logback = "1.5.14"
+logback = "1.5.15"
 scrimage = "4.3.0"
 twelvemonkeys = "3.12.0"