Update conf.py

Author: mcbarton

docs/source/conf.py

@@ -13,6 +13,7 @@
                           curl -Ls https://micro.mamba.pm/api/micromamba/linux-64/latest | tar -xvj -C "$HOME/micromamba" bin/micromamba;\
                           export PATH="$HOME/micromamba/bin/:$PATH";\
                           export MAMBA_ROOT_PREFIX="$HOME/micromamba/";\
+                          eval "$(micromamba shell hook --shell )";\
                           micromamba create -f environment-wasm-build.yml -y;\
                           micromamba activate xeus-cpp-wasm-build;\
                           micromamba create -f environment-wasm-host.yml --platform=emscripten-wasm32;\