feat(docker): add 3.14 beta images to uv docker (#13390)

## Summary

Now that Python 3.14 first beta is out, I think it's worth adding
support for the official upstream RC images.

Once 3.14 is released, we can remove the `-rc-` infix from the images we
pull from.

## Test Plan

Upstream images verified to be functional with uv.

Author: samypr100

.github/workflows/build-docker.yml

@@ -191,18 +191,21 @@ jobs:
           - alpine:3.21,alpine3.21,alpine
           - debian:bookworm-slim,bookworm-slim,debian-slim
           - buildpack-deps:bookworm,bookworm,debian
+          - python:3.14-rc-alpine,python3.14-rc-alpine
           - python:3.13-alpine,python3.13-alpine
           - python:3.12-alpine,python3.12-alpine
           - python:3.11-alpine,python3.11-alpine
           - python:3.10-alpine,python3.10-alpine
           - python:3.9-alpine,python3.9-alpine
           - python:3.8-alpine,python3.8-alpine
+          - python:3.14-rc-bookworm,python3.14-rc-bookworm
           - python:3.13-bookworm,python3.13-bookworm
           - python:3.12-bookworm,python3.12-bookworm
           - python:3.11-bookworm,python3.11-bookworm
           - python:3.10-bookworm,python3.10-bookworm
           - python:3.9-bookworm,python3.9-bookworm
           - python:3.8-bookworm,python3.8-bookworm
+          - python:3.14-rc-slim-bookworm,python3.14-rc-bookworm-slim
           - python:3.13-slim-bookworm,python3.13-bookworm-slim
           - python:3.12-slim-bookworm,python3.12-bookworm-slim
           - python:3.11-slim-bookworm,python3.11-bookworm-slim

docs/guides/integration/docker.md

@@ -38,30 +38,33 @@ The following distroless images are available:
 And the following derived images are available:
 
 <!-- prettier-ignore -->
-- Based on `alpine:3.20`:
+- Based on `alpine:3.21`:
     - `ghcr.io/astral-sh/uv:alpine`
-    - `ghcr.io/astral-sh/uv:alpine3.20`
+    - `ghcr.io/astral-sh/uv:alpine3.21`
 - Based on `debian:bookworm-slim`:
     - `ghcr.io/astral-sh/uv:debian-slim`
     - `ghcr.io/astral-sh/uv:bookworm-slim`
 - Based on `buildpack-deps:bookworm`:
     - `ghcr.io/astral-sh/uv:debian`
     - `ghcr.io/astral-sh/uv:bookworm`
 - Based on `python3.x-alpine`:
+    - `ghcr.io/astral-sh/uv:python3.14-rc-alpine`
     - `ghcr.io/astral-sh/uv:python3.13-alpine`
     - `ghcr.io/astral-sh/uv:python3.12-alpine`
     - `ghcr.io/astral-sh/uv:python3.11-alpine`
     - `ghcr.io/astral-sh/uv:python3.10-alpine`
     - `ghcr.io/astral-sh/uv:python3.9-alpine`
     - `ghcr.io/astral-sh/uv:python3.8-alpine`
 - Based on `python3.x-bookworm`:
+    - `ghcr.io/astral-sh/uv:python3.14-rc-bookworm`
     - `ghcr.io/astral-sh/uv:python3.13-bookworm`
     - `ghcr.io/astral-sh/uv:python3.12-bookworm`
     - `ghcr.io/astral-sh/uv:python3.11-bookworm`
     - `ghcr.io/astral-sh/uv:python3.10-bookworm`
     - `ghcr.io/astral-sh/uv:python3.9-bookworm`
     - `ghcr.io/astral-sh/uv:python3.8-bookworm`
 - Based on `python3.x-slim-bookworm`:
+    - `ghcr.io/astral-sh/uv:python3.14-rc-bookworm-slim`
     - `ghcr.io/astral-sh/uv:python3.13-bookworm-slim`
     - `ghcr.io/astral-sh/uv:python3.12-bookworm-slim`
     - `ghcr.io/astral-sh/uv:python3.11-bookworm-slim`