teams/ngi: fix office hours (#1949)

Office hours times were given in UTC and they don't account for the
pesky DST rules.

Setting it up to UTC+2 and giving Central European Summer Time (CEST) as
reference.

Author: wamirez

core/src/content/teams/160_ngi.mdx

@@ -72,7 +72,7 @@ These are the people we work for and with:
   - [Reports on past Summers of Nix](https://github.com/ngi-nix/summer-of-nix?#annual-reports)
 - If you’re a current or past NGI Zero grantee: Contact us for free Nix training, pair programming, or support with getting your software to NixOS.
 
-For questions or comments, please [contact the team](https://github.com/ngi-nix/summer-of-nix#contact) or join our [office hours on Jitsi](https://jitsi.lassul.us/ngi-nix-office-hours) every [Tuesday and Thursday from 13:00 to 14:00 UTC](https://calendar.google.com/calendar/u/0/embed?src=b9o52fobqjak8oq8lfkhg3t0qg@group.calendar.google.com).
+For questions or comments, please [contact the team](https://github.com/ngi-nix/summer-of-nix#contact) or join our [office hours on Jitsi](https://jitsi.lassul.us/ngi-nix-office-hours) every [Tuesday and Thursday from 16:00 to 17:00 UTC+2 (CEST)](https://calendar.google.com/calendar/u/0/embed?src=b9o52fobqjak8oq8lfkhg3t0qg@group.calendar.google.com).
 
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