Add JVM-argument --add-opens to fix Reload Configurations classloading issue

[jkosternl]

1. Add JVM-argument --add-opens to fix Reload Configurations classloading issue
2. ignore IntelliJ folder for Git

Fix 1 is needed if you click at Reload Configurations in the console. Without it, the -add-opens parameters are not correctly pass through the classloaders who are trying to load the classes in the Configurations used. The first load of configurations works fine, but reloads are failing with:
2024-03-13 10:52:02,045 ERROR [http-nio-80-exec-9] {} lifecycle.ApplicationMessageEvent - Application [MyFirstFrank] an exception occurred while loading configuration [IAF_Util] java.lang.NullPointerException: Cannot invoke "String.hashCode()" because "<local2>" is null

With the default examples inside frank-runner I did not get this reproduced. But with the Academy project ../MyFirstFrank it happened.
Adding this jvmargs fixes the below class loading issue and the previous strange NPE is gone as well.

Here is the used configuration (renamed, because GitHub refuses .xml files):
Configuration.xml.txt

Part of the stacktrace which is solved by this PR:

2024-03-13 10:52:02,016 ERROR [http-nio-80-exec-9] {} digester3.Digester - Begin event threw exception
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.frankframework.jdbc.XmlQuerySender': 
Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not 
generate CGLIB subclass of class org.frankframework.jdbc.XmlQuerySender: Common causes of this problem include 
using a final class or a non-visible class; nested exception is org.springframework.cglib.core.ReflectUtils$6:
 ClassLoader mismatch for [org.frankframework.jdbc.XmlQuerySender]: JVM should be started with 
--add-opens=java.base/java.lang=ALL-UNNAMED for ClassLoader.defineClass to be accessible on 
org.frankframework.configuration.classloaders.WebAppClassLoader; consider co-locating the affected class in that 
target ClassLoader instead.