Add script after setting scripts in RsrcDbPopultr

Prior to this commit it was impossible to add additional scripts to a
ResourceDatabasePopulator after setScripts() had been invoked.

This commit fixes this by ensuring that the internal scripts list
continues to be modifiable when setScripts() is invoked.

Issue: SPR-11691

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/ResourceDatabasePopulator.java

@@ -133,7 +133,8 @@ public class ResourceDatabasePopulator implements DatabasePopulator {
 	 */
 	public void setScripts(Resource... scripts) {
 		assertContentsOfScriptArray(scripts);
-		this.scripts = Arrays.asList(scripts);
+		// Ensure that the list is modifiable
+		this.scripts = new ArrayList<Resource>(Arrays.asList(scripts));
 	}
 
 	/**