Skip SIG Std/Cert on 2025-09-25 due to concurrent meeting (#388)

* Skip SIG Std/Cert 2025-09-25, 2025-10-02 due to conferences
* Remove exception for 2025-10-02

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Signed-off-by: Matthias Büchse <[email protected]>

Author: mbuechse

teams/sig_standard_cert/team_meetings.yml

@@ -88,3 +88,4 @@ events:
         - 2025-06-05 14:05:00  # because of FOCIS hackathon
         - 2025-06-19 14:05:00  # public holiday in southern Germany, and others are gone as well
         - 2025-08-14 14:05:00  # holiday season; most people are on vacation
+        - 2025-09-25 14:05:00  # SCS summit hangover, meeting of Forum SCS-Standards