Revert "Use Gradle's new daemon JVM criteria feature"

This causes problems on IntelliJ IDEA's 2025.1 EAP version which picks
the IDE's own JetBrains JDK rather than one specified using the `JDK21`
env var. Since JetBrains' JDK does not contain tools like `jar` this
causes builds to break when the Gradle daemon is started via IntelliJ
IDEA.

This reverts commit 1e29d8e.

Author: marcphilipp

gradle/gradle-daemon-jvm.properties

@@ -1,3 +1,9 @@
+val expectedJavaVersion = JavaVersion.VERSION_21
+val actualJavaVersion = JavaVersion.current()
+require(actualJavaVersion == expectedJavaVersion) {
+	"The JUnit 5 build must be executed with Java ${expectedJavaVersion.majorVersion}. Currently executing with Java ${actualJavaVersion.majorVersion}."
+}
+
 dependencyResolutionManagement {
 	versionCatalogs {
 		create("libs") {