minor #12864 Update multiple_guard_authenticators.rst (atailouloute)

This PR was merged into the 4.3 branch.

Discussion
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Update multiple_guard_authenticators.rst

Add missing entry_point authenticator in PHP example

Commits
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ff6ce21 Update multiple_guard_authenticators.rst

Author: javiereguiluz

security/multiple_guard_authenticators.rst

@@ -68,7 +68,7 @@ This is how your security configuration can look in action:
                 'default' => [
                     'anonymous' => null,
                     'guard' => [
-                        'entry_point' => '',
+                        'entry_point' => LoginFormAuthenticator::class,
                         'authenticators' => [
                             LoginFormAuthenticator::class,
                             FacebookConnectAuthenticator::class,