Chnage email to UNSW

Signed-off-by: Gernot Heiser <gernot@unsw.edu.au>

Foundation/Summit/2024/social-activities.html

@@ -36,7 +36,7 @@ <h4 style="padding-top:20px">Blue Mountains bush walk</h4>
  <p>
  Gernot plans to take a group on a walk in the
  stunning <a href="https://www.visitnsw.com/destinations/blue-mountains">Blue
- Mountains</a>, weather permitting. Please contact <a title="gernot@unsw.edu.au" href="mailto:gernot@sel4.systems">Gernot Heiser</a> for further details.
+ Mountains</a>, weather permitting. Please contact <a title="gernot@unsw.edu.au" href="mailto:gernot@unsw.edu.au">Gernot Heiser</a> for further details.
  </p>
  <p>
  <strong>When:</strong> Sunday 13 Oct 2024
@@ -83,7 +83,7 @@ <h4 style="padding-top:20px">Blue Mountains bush walk</h4>
  <strong>08:15</strong> meet at Central Station <s>Platform 5</s>
  <strong style="color:red">Platform 18</strong> to
  take the <s>8:24 train to Lithgow, arrive Katoomba
- 10:29</s><strong style="color:red">8:21 train to Hornsby, arrive Katoomba
+ 10:29</s> <strong style="color:red">8:21 train to Hornsby, arrive Katoomba
  10:54</strong> (with changing to a bus and back to train in between).<br/> For
  those staying at the Summit venue (Potts Point Holiday Inn),
  King's Cross station is practically next door.
@@ -125,8 +125,8 @@ <h4 style="padding-top:20px">Blue Mountains bush walk</h4>
  </p>
 
  <p>
- <strong>Important:</strong> Let <a title="gernot@sel4.systems"
- href="mailto:gernot@sel4.systems">Gernot</a>
+ <strong>Important:</strong> Let <a title="gernot@unsw.edu.au"
+ href="mailto:gernot@unsw.edu.au">Gernot</a>
  know if you're coming so we can make sure we've
  got everyone when we take the train!
  </p>