ci: Introduce no-plain-errors lint rule for BE packages (no-changelog) (#7961)

## Summary
Require `ApplicationError` or its child classes instead of plain `Error`
in BE packages. This ensures the error will be normalized when reported
to Sentry, if applicable.

Follow-up to:
https://github.com/n8n-io/n8n/pulls?q=is%3Apr+is%3Aclosed+applicationerror

...

#### How to test the change:
1. ...


## Issues fixed
Include links to Github issue or Community forum post or **Linear
ticket**:
> Important in order to close automatically and provide context to
reviewers

...


## Review / Merge checklist
- [ ] PR title and summary are descriptive. **Remember, the title
automatically goes into the changelog. Use `(no-changelog)` otherwise.**
([conventions](https://github.com/n8n-io/n8n/blob/master/.github/pull_request_title_conventions.md))
- [ ] [Docs updated](https://github.com/n8n-io/n8n-docs) or follow-up
ticket created.
- [ ] Tests included.
> A bug is not considered fixed, unless a test is added to prevent it
from happening again. A feature is not complete without tests.
  >
> *(internal)* You can use Slack commands to trigger [e2e
tests](https://www.notion.so/n8n/How-to-use-Test-Instances-d65f49dfc51f441ea44367fb6f67eb0a?pvs=4#a39f9e5ba64a48b58a71d81c837e8227)
or [deploy test
instance](https://www.notion.so/n8n/How-to-use-Test-Instances-d65f49dfc51f441ea44367fb6f67eb0a?pvs=4#f6a177d32bde4b57ae2da0b8e454bfce)
or [deploy early access version on
Cloud](https://www.notion.so/n8n/Cloudbot-3dbe779836004972b7057bc989526998?pvs=4#fef2d36ab02247e1a0f65a74f6fb534e).

packages/nodes-base/nodes/Kafka/Kafka.node.ts

@@ -14,7 +14,7 @@ import type {
 	INodeType,
 	INodeTypeDescription,
 } from 'n8n-workflow';
-import { NodeOperationError } from 'n8n-workflow';
+import { ApplicationError, NodeOperationError } from 'n8n-workflow';
 import { generatePairedItemData } from '../../utils/utilities';
 
 export class Kafka implements INodeType {
@@ -229,7 +229,10 @@ export class Kafka implements INodeType {
 					};
 					if (credentials.authentication === true) {
 						if (!(credentials.username && credentials.password)) {
-							throw Error('Username and password are required for authentication');
+							// eslint-disable-next-line n8n-nodes-base/node-execute-block-wrong-error-thrown
+							throw new ApplicationError('Username and password are required for authentication', {
+								level: 'warning',
+							});
 						}
 						config.sasl = {
 							username: credentials.username as string,