Bump caddy from 2.8.0 to 2.8.1 in /caddy-cloudflare

Bumps caddy from 2.8.0 to 2.8.1.

---
updated-dependencies:
- dependency-name: caddy
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

caddy-cloudflare/Dockerfile

@@ -1,10 +1,10 @@
 # syntax=docker/dockerfile:1
-FROM caddy:2.8.0-builder AS builder
+FROM caddy:2.8.1-builder AS builder
 
 RUN xcaddy build \
     --with github.com/caddy-dns/cloudflare \
     --with github.com/WeidiDeng/caddy-cloudflare-ip
 
-FROM caddy:2.8.0
+FROM caddy:2.8.1
 
 COPY --from=builder /usr/bin/caddy /usr/bin/caddy