minor #20816 Add Tugdual Saunier as a core team member (fabpot)

This PR was merged into the 6.4 branch.

Discussion
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Add Tugdual Saunier as a core team member

See https://symfony.com/blog/new-core-team-member-symfony-cli

Commits
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5f722a3 Add Tugdual Saunier as a core team member

Author: javiereguiluz

Diff for: contributing/core_team.rst

@@ -86,6 +86,7 @@ Active Core Members
   * **Berislav Balogović** (`hypemc`_);
   * **Mathias Arlaud** (`mtarld`_);
   * **Florent Morselli** (`spomky`_);
+  * **Tugdual Saunier** (`tucksaun`_);
   * **Alexandre Daubois** (`alexandre-daubois`_).
 
 * **Security Team** (``@symfony/security`` on GitHub):
@@ -263,3 +264,4 @@ discretion of the **Project Leader**.
 .. _`mtarld`: https://github.com/mtarld/
 .. _`spomky`: https://github.com/spomky/
 .. _`alexandre-daubois`: https://github.com/alexandre-daubois/
+.. _`tucksaun`: https://github.com/tucksaun/