Fix doc generation on release
Fix doc generation on release

* Re-order version fetching
* use node images to remove the node setup on workflow
* Correct paths for publish and destination dirs for pages
* Update the index file updation script to writeback the output
* Update commit action to v2.9 to remove safe directory issue
(https://github.com/actions/checkout/issues/760)

Signed-off-by: Abhinav Krishna C K <b1c1d8736f20db3fb6c1c66bb1455ed43909f0d8@abhy.me>

matrix-org/matrix-appservice-bridge,matrix-org/matrix-appservice-bridge,matrix-org/matrix-appservice-bridge