Update docker.io/caddy:2.9.1-alpine Docker digest to b4e3952 (#49)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker.io/caddy | final | digest | `b606366` -> `b4e3952` |

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Dockerfile

@@ -59,7 +59,7 @@ COPY . .
 COPY --from=snapshot-versions-getter ./melpa_snapshot_versions.json ./TODAY ./
 RUN env TODAY="$(cat TODAY)" npx tsx gen_caddy.ts > Caddyfile
 
-FROM docker.io/caddy:2.9.1-alpine@sha256:b60636634fd2aebaf9460cf60997ad83aad6b139318d5713e2b78a60f52b139c
+FROM docker.io/caddy:2.9.1-alpine@sha256:b4e3952384eb9524a887633ce65c752dd7c71314d2c2acf98cd5c715aaa534f0
 
 LABEL org.opencontainers.image.authors="Hong Xu <[email protected]>"
 LABEL org.opencontainers.image.title="Delpa Redirection Server"