Raise myst-nb execution timeout to fix flaky Read the Docs builds (#495)

The logo animation notebook (docs/source/logo.md) renders 360 frames and
encodes them with libvpx-vp9, which takes close to 3 minutes on Read the
Docs builders. The 180 s nb_execution_timeout was intermittently exceeded,
causing docs builds to fail with CellTimeoutError.

Author: basnijholt

docs/source/conf.py

@@ -79,7 +79,9 @@
 
 # myst-nb configuration
 nb_execution_mode = "cache"
-nb_execution_timeout = 180
+# Generating the logo animation (logo.md) takes ~3 minutes on Read the Docs
+# builders, which intermittently exceeded the previous 180 s limit.
+nb_execution_timeout = 600
 nb_execution_raise_on_error = True