Re-add syntax highlighting to daily emails and

...ATDC lessons

source/_daily_emails/2023-11-18.md

@@ -16,7 +16,7 @@ In PHPUnit, there are different ways to write test methods.
 
 The standard way is to use camel-case method names with a `test` prefix, for example:
 
-```php
+```language-php
 public function testTheProjectNameShouldBeAString(): void
 {
     // ...
@@ -25,7 +25,7 @@ public function testTheProjectNameShouldBeAString(): void
 
 Another popular way, particularly in some frameworks, is to use snake-case method names:
 
-```php
+```language-php
 /** @test */
 public function the_project_name_should_be_a_string(): void
 {