[CI] Remove the unnecessary workflow related functorch (#162581)

The [docs](https://docs.pytorch.org/functorch/stable/) about `functorch` has been migrated into [PyTorch Doc](https://docs.pytorch.org/docs/stable/func.html) since PyTorch 2.0, so I think we can remove it right now to reduce the compute resources usages.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/162581
Approved by: https://github.com/ezyang

.circleci/scripts/functorch_doc_push_script.sh

@@ -1,47 +0,0 @@
-#!/bin/bash
-# =================== The following code **should** be executed inside Docker container ===================
-
-# Install dependencies
-sudo apt-get -y update
-sudo apt-get -y install expect-dev
-
-# This is where the local pytorch install in the docker image is located
-pt_checkout="/var/lib/jenkins/workspace"
-source "$pt_checkout/.ci/pytorch/common_utils.sh"
-echo "functorch_doc_push_script.sh: Invoked with $*"
-
-set -ex
-
-version=${DOCS_VERSION:-nightly}
-echo "version: $version"
-
-# Build functorch docs
-pushd $pt_checkout/functorch/docs
-pip -q install -r requirements.txt
-make html
-popd
-
-git clone https://github.com/pytorch/functorch -b gh-pages --depth 1 functorch_ghpages
-pushd functorch_ghpages
-
-if [ $version == "main" ]; then
-  version=nightly
-fi
-
-git rm -rf "$version" || true
-mv "$pt_checkout/functorch/docs/build/html" "$version"
-
-git add "$version" || true
-git status
-git config user.email "soumith+bot@pytorch.org"
-git config user.name "pytorchbot"
-# If there aren't changes, don't make a commit; push is no-op
-git commit -m "Generate Python docs from pytorch/pytorch@${GITHUB_SHA}" || true
-git status
-
-if [[ "${WITH_PUSH:-}" == true ]]; then
-  git push -u origin gh-pages
-fi
-
-popd
-# =================== The above code **should** be executed inside Docker container ===================