Install xvfb in RTD environment

dstansby · dstansby · commit 432fb7a65145 · 2023-05-10T11:29:02.000+01:00
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
@@ -13,3 +13,4 @@ build:
     python: "3.10"
   apt_packages:
     - qtbase5-dev
+    - xvfb
