update finaid receipt submission deadline

Author: hypha

src/content/pages/finaid.mdx

@@ -103,7 +103,7 @@ early.**
 | 6 June 2025 | ![round two](/finaid-round2.svg) | Deadline to accept a second-round grant |
 | 7 July 2025 | | Remote Ticket grant applications open |
 | **15 July 2025** | | **Deadline for submitting Remote Ticket grant applications** |
-| 25 July 2025 || Deadline for submitting receipts/invoices |
+| 28 July 2025 || Deadline for submitting receipts/invoices |
 
 _Thank you to everyone who applied—see you in Prague!_
 
@@ -160,7 +160,7 @@ In addition, please pay close attention to the following:
   due to sanctions or international regulations.
 - Reimbursements will only be made after we’ve received your
   travel/accommodation receipts/invoices. The deadline to submit your
-  receipts/invoices is **25 July 2025** [Anywhere on Earth][AoE].
+  receipts/invoices is **28 July 2025** [Anywhere on Earth][AoE].
 - Please make sure that your receipts/invoices contain the information necessary
   for us to validate them. At the very least, they should contain your name, the
   date, the amount, and specify what the receipt/invoice is for.