minor symfony#26604 [Console] Fix docblock of DescriptorInterface::describe (codedmonkey)

This PR was merged into the 2.7 branch.

Discussion
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[Console] Fix docblock of DescriptorInterface::describe

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes?

This might be the smallest commit ever, but I came across this docblock which seems to be incorrectly copied from https://github.com/symfony/symfony/blob/7101893b51cf6d6e2a9bc131eadefa0a02151d11/src/Symfony/Component/Console/Descriptor/Descriptor.php#L74 and it threw me off guard for a moment when I read it.

I can see more improvements being made (like mentioning the `InvalidArgumentException`) but I didn't want to overdo it.

Commits
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dad27b0 [Console] Fix docblock of DescriptorInterface::describe

Author: fabpot

src/Symfony/Component/Console/Descriptor/DescriptorInterface.php

@@ -21,7 +21,7 @@
 interface DescriptorInterface
 {
     /**
-     * Describes an InputArgument instance.
+     * Describes an object if supported.
      *
      * @param OutputInterface $output
      * @param object          $object