Merge branch '2.2.x' into 2.3.x

Closes gh-23341

Author: snicoll

spring-boot-project/spring-boot-dependencies/build.gradle

@@ -981,6 +981,9 @@ bom {
 		}
 	}
 	library("Kotlin Coroutines", "1.3.8") {
+		prohibit("[1.3.9,)") {
+			because "it requires Kotlin 1.4"
+		}
 		group("org.jetbrains.kotlinx") {
 			imports = [
 				"kotlinx-coroutines-bom"