Update plugins/src/main/java/com/google/firebase/gradle/plugins/semver/DeltaType.kt

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: rlazo

plugins/src/main/java/com/google/firebase/gradle/plugins/semver/DeltaType.kt

@@ -205,7 +205,7 @@ enum class DeltaType {
               after.name,
               field!!.name,
               String.format(
-                "Field %s on class %s has increased its visiblity.",
+                "Field %s on class %s has reduced its visiblity.",
                 field.name,
                 after.name,
               ),