minor #15088 Update kernel.rst (94noni)

This PR was merged into the 4.4 branch.

Discussion
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Update kernel.rst

I am unsure of this change, wdyt?
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Commits
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ce6cdbe Update kernel.rst

Author: OskarStark

reference/configuration/kernel.rst

@@ -5,7 +5,7 @@ Configuring in the Kernel
 =========================
 
 Some configuration can be done on the kernel class itself (located by default at
-``src/Kernel.php``). You can do this by overriding specific methods in
+``src/Kernel.php``). You can do this by overriding specific methods of
 the parent :class:`Symfony\\Component\\HttpKernel\\Kernel` class.
 
 Configuration