feature #19487 Document secrets:reveal command (danielburger1337)

This PR was squashed before being merged into the 7.1 branch.

Discussion
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Document `secrets:reveal` command

Document the new `secrets:reveal` command.

Docs Issue: #19481
Feature PR: symfony/symfony#53466

Commits
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22ad2d9 Document `secrets:reveal` command

Author: OskarStark

configuration/secrets.rst

@@ -166,6 +166,22 @@ secrets' values by passing the ``--reveal`` option:
       DATABASE_PASSWORD   "my secret"
      ------------------- ------------ -------------
 
+Reveal Existing Secrets
+-----------------------
+
+If you have the **decryption key**, the ``secrets:reveal`` command allows
+you to reveal a single secrets value.
+
+.. code-block:: terminal
+
+    $ php bin/console secrets:reveal DATABASE_PASSWORD
+
+     my secret
+
+.. versionadded:: 7.1
+
+    The ``secrets:reveal`` command was introduced in Symfony 7.1.
+
 Remove Secrets
 --------------