Fix broken room URLs #1

So for some rooms the URL in TISS changed, which besides bad practise
as URLs should be permanent also broke some assumptions we had in
our room generating script.

However, the script is now more robust but changing urls will always
require us to rerun the script.

app/resources/generate_rooms.py

@@ -36,8 +36,9 @@ def main():
                 cells = row.find_elements(By.CSS_SELECTOR, "td")
                 room = [cell.text for cell in cells]
                 room.append(
-                    "https://tiss.tuwien.ac.at/events/roomSchedule.xhtml?roomCode="
-                    + room[7]
+                    cells[0]
+                    .find_elements(By.CSS_SELECTOR, "a")[0]
+                    .get_attribute("href")
                 )
                 data.append(room)