Added new abstract deadline for S&P (#5)

Author: andreasbrueg

_data/conferences.yml

@@ -84,6 +84,7 @@
   description: IEEE Symposium on Security and Privacy
   year: 2026  
   link: https://sp2026.ieee-security.org/
+  abdeadline: May 29, November 6
   deadline:
     - "2025-06-05 23:59"
     - "2025-11-13 23:59"
@@ -1227,4 +1228,4 @@
   portal: https://www.editorialmanager.com/jpdc/
   comment: Accepts submission throughout the year.
   tags: [THEORY, PRACT, JRN]
-  
+