Fix block selector not closing after pasting block

Fixes getkirby#7087

Add a `close` method to the `BlockSelector` component to fix the issue of the block selector not closing after pasting a block.

* Add a `close` method in the `methods` section of `panel/src/components/Forms/Blocks/BlockSelector.vue`.
* Call the `close` method after pasting a block to close the block selector.
* Emit a `cancel` event in the `close` method to handle the closing of the block selector.

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Author: fnwbr

panel/src/components/Forms/Blocks/BlockSelector.vue

@@ -122,6 +122,10 @@ export default {
 		paste(e) {
 			this.$emit("paste", e);
 			this.close();
+			this.close();
+		},
+		close() {
+			this.$emit("cancel");
 		}
 	}
 };