webhook edit: make items config not static

modifying static elements from the class, like done here with e.g.

 me.items[0][key] = value;

is dangerous, since it directly modifies the class definition of those
arrays/objects.

Instead move the definition in initComponent, which uses a fresh
declaration each time the component is initialized.

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

src/panel/WebhookEditPanel.js

@@ -318,7 +318,10 @@ Ext.define('Proxmox.form.WebhookKeyValueList', {
 	},
     },
 
-    items: [
+    initComponent: function() {
+	let me = this;
+
+	let items = [
 	    {
 		xtype: 'grid',
 		reference: 'grid',
@@ -338,23 +341,7 @@ Ext.define('Proxmox.form.WebhookKeyValueList', {
 		    },
 		},
 		margin: '5 0 5 0',
-	},
+		columns: [
-	{
-	    xtype: 'button',
-	    text: gettext('Add'),
-	    iconCls: 'fa fa-plus-circle',
-	    handler: 'addLine',
-	},
-    ],
-
-    initComponent: function() {
-	let me = this;
-
-	for (const [key, value] of Object.entries(me.gridConfig ?? {})) {
-	    me.items[0][key] = value;
-	}
-
-	me.items[0].columns = [
 		    {
 			header: me.fieldTtitle,
 			dataIndex: 'headerName',
@@ -400,8 +387,24 @@ Ext.define('Proxmox.form.WebhookKeyValueList', {
 			    iconCls: 'fa fa-trash-o',
 			},
 		    },
+		],
+	    },
+	    {
+		xtype: 'button',
+		text: gettext('Add'),
+		iconCls: 'fa fa-plus-circle',
+		handler: 'addLine',
+	    },
 	];
 
+	for (const [key, value] of Object.entries(me.gridConfig ?? {})) {
+	    items[0][key] = value;
+	}
+
+	Ext.apply(me, {
+	    items,
+	});
+
 	me.callParent();
 	me.initField();
     },