chore(deps): update caddy docker tag to v2.8.4 (#106)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| caddy | final | patch | `2.8.1-alpine` -> `2.8.4-alpine` |

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Reviewed-on: #106
Reviewed-by: OCram85 <marco.blessing@googlemail.com>
Co-authored-by: renovate-bot <renovate@ocram85.com>
Co-committed-by: renovate-bot <renovate@ocram85.com>

Dockerfile.vitepress

@@ -6,7 +6,7 @@ ENV NODE_ENV=production
 RUN bun install --frozen-lockfile
 RUN bun run --vite docs:build
 
-FROM caddy:2.8.1-alpine as prod
+FROM caddy:2.8.4-alpine as prod
 
 COPY --from=builder /app/docs/.vitepress/dist/ /arkanum-docs/
 COPY Caddyfile /etc/caddy