POM: update parent to pom-scijava 40.0.0

And target a minimum of Java 21 when building.

pom.xml

@@ -4,7 +4,7 @@
 	<parent>
 		<groupId>org.scijava</groupId>
 		<artifactId>pom-scijava</artifactId>
-		<version>40.0.0-SNAPSHOT</version>
+		<version>40.0.0</version>
 		<relativePath />
 	</parent>
 
@@ -132,7 +132,7 @@
 		<license.projectName>Fiji distribution of ImageJ for the life sciences.</license.projectName>
 		<license.excludes>%regex[.*main/resources/.*|.*/macros/.*]</license.excludes>
 
-		<scijava.jvm.version>11</scijava.jvm.version>
+		<scijava.jvm.version>21</scijava.jvm.version>
 		<doclint>none</doclint>
 
 		<!-- TEMP: Avoid javadoc build errors due to JPMS complexity. -->
@@ -143,9 +143,6 @@
 		<!-- TEMP: Avoid SNTService initialization error in Java21. -->
 		<maven.test.skip>true</maven.test.skip>
 
-		<!-- TEMP: Avoid NPE from maven-enforcer-plugin 3.3.0 execution -->
-		<enforcer.skip>true</enforcer.skip>
-
 		<!-- Dependency versions -->
 		<annotations.version>24.1.0</annotations.version>
 		<fastutil-core.version>8.5.13</fastutil-core.version>