Merge branch 'update-staff-pages' into 'main'

Update 2 files

See merge request !8

_staffers/gui.md

+---
+name: Gui Alvarenga
+role: Teaching Assistant
+email: g.ferreirasecodealvarenga@student.tudelft.nl
+photo: Gui.jpg
+---
+
+Civil Engineering / Geoscience & Remote Sensing
\ No newline at end of file

_staffers/isabel.md

+---
+name: Isabel Slingerland
+role: Teaching Assistant
+email: I.C.SLingerland-1@student.tudelft.nl
+photo: Isabel.jpeg
+---
+Civil Engineering / Geoscience & Remote Sensing
\ No newline at end of file

_staffers/mohammed.md

+---
+name: Mohammed Shomis
+role: Teaching Assistant
+email: M.S.A.Shomis@student.tudelft.nl
+photo: Mohammed.JPG
+---
+
+Computer Science / Software Development