Replace deprecated action with RtD app (#149111)

.github/workflows/documentation-links.yml

@@ -1,28 +0,0 @@
-name: Read the Docs PR preview
-# Automatically edits a pull request's descriptions with a link
-# to the documentation's preview on Read the Docs.
-
-on:
-  pull_request_target:
-    types:
-      - opened
-    paths:
-    - 'Doc/**'
-    - '.github/workflows/doc.yml'
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
-  cancel-in-progress: true
-
-jobs:
-  documentation-links:
-    runs-on: ubuntu-latest
-    permissions:
-      pull-requests: write
-    timeout-minutes: 5
-
-    steps:
-      - uses: readthedocs/actions/preview@b8bba1484329bda1a3abe986df7ebc80a8950333 # v1.5
-        with:
-          project-slug: "cpython-previews"
-          single-version: "true"