minor #5363 Added missing self return type to ConfigInterface::regist…

…erCustomFixers() (vudaltsov)

This PR was merged into the 2.17 branch.

Discussion
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Added missing self return type to ConfigInterface::registerCustomFixers()

Commits
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001cdd2 Added missing self return type to ConfigInterface::registerCustomFixers()

src/ConfigInterface.php

@@ -108,6 +108,8 @@ public function getUsingCache();
      * Name of custom fixer should follow `VendorName/rule_name` convention.
      *
      * @param FixerInterface[]|iterable|\Traversable $fixers
+     *
+     * @return self
      */
     public function registerCustomFixers($fixers);