Finder::path() method matching directories and files

For clarity, adds an example where `path()` is used to match a directory or a file.

ref api-platform/core#575 (comment)

Author: soyuka

components/finder.rst

@@ -223,6 +223,11 @@ The :method:`Symfony\\Component\\Finder\\Finder::notPath` method excludes files
 
     $finder->notPath('other/dir');
 
+The method :method:`Symfony\\Component\\Finder\\Finder::path` matches both directories and files. For example, the following will match ``foo/bar.yml`` but also ``foo.yml``::
+
+    $finder->in(__DIR__)->path('foo')->name('*.yml);
+
+
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