[Doc] Add setuptools dependency for building docs (ray-project#46375)

This PR:

- Adds a _temporary_ `setuptools>=70.0.0` dependency for building the
docs to make `sphinxcontrib-redoc` usable on Python 3.12. This is not
intended to be a long term solution, so ray-project#46374 has been made to track
the follow-up work.
- Remove unused environment variable in the buildkite job that builds
docs
- Bump the os version and python version used to build the docs on RTD

Signed-off-by: pdmurray <[email protected]>

Author: peytondmurray

.buildkite/build.rayci.yml

@@ -45,7 +45,7 @@ steps:
     key: doc_build
     instance_type: medium
     commands:
-      - FAST=True make -C doc/ html
+      - make -C doc/ html
     depends_on: docbuild
     job_env: docbuild
 

.readthedocs.yaml

@@ -7,9 +7,9 @@ version: 2
 
 # Set the version of Python and other tools you might need
 build:
-  os: ubuntu-22.04
+  os: ubuntu-24.04
   tools:
-    python: "3.11"
+    python: "3.12"
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:

doc/requirements-doc.txt

@@ -1,5 +1,8 @@
 # Production requirements. This is what readthedocs.com picks up
 
+# Required to build the docs on 3.12 due to pkg_resources deprecation
+setuptools>=70.0.0
+
 # Syntax highlighting
 Pygments==2.16.1