fix: event DBQuery is not fired on failed query when DBDebug is true

[kenjis]

Description

DBQuery
This event is triggered whenever a new query has been run, whether successful or not.
https://codeigniter4.github.io/CodeIgniter4/database/events.html#the-events

But the event DBQuery is not fired on failed query when DBDebug is true.

• fix BaseConnection
• fix user guide

How to Test

--- a/app/Config/Events.php
+++ b/app/Config/Events.php
@@ -46,3 +46,8 @@ Events::on('pre_system', static function () {
         Services::toolbar()->respond();
     }
 });
+
+Events::on(
+    'DBQuery',
+    static function (\CodeIgniter\Database\Query $query) { log_message('alert', (string) $query); }
+);
diff --git a/app/Controllers/Home.php b/app/Controllers/Home.php
index 7f867e95f..492606d92 100644
--- a/app/Controllers/Home.php
+++ b/app/Controllers/Home.php
@@ -6,6 +6,8 @@ class Home extends BaseController
 {
     public function index()
     {
+        db_connect()->query('select * from bad_table where a = 1');
+
         return view('welcome_message');
     }
 }

Navigate to http://localhost:8080/ and see log file.

Before:

ERROR - 2022-06-14 22:11:50 --> Table 'ci4.bad_table' doesn't exist
CRITICAL - 2022-06-14 22:11:50 --> Table 'ci4.bad_table' doesn't exist

After:

ERROR - 2022-06-14 22:13:32 --> Table 'ci4.bad_table' doesn't exist
ALERT - 2022-06-14 22:13:32 --> select * from bad_table where a = 1
CRITICAL - 2022-06-14 22:13:32 --> Table 'ci4.bad_table' doesn't exist

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[MGatner]

A step in the right direction.