lib: event static properties non writable and configurable

The idl definition for Event makes the properties constant
this means that they shouldn't be configurable and writable.
However, they were, and this commit fixes that.

Fixes: nodejs#50417

test/parallel/test-event-target.js

@@ -12,11 +12,8 @@ const eventPhases = {
 
 // Using Object.keys to get the properties from the Event object
 const eventKeys = Object.keys(Event);
-console.log(eventKeys);
 
 for (const [prop, value] of Object.entries(eventPhases)) {
-  console.log(prop);
-  console.log(value);
   // Check if the property exists in the Event object
   assert.ok(eventKeys.includes(prop), `Event does not have the property: ${prop}`);