chore(deps): update oven/bun docker tag to v1.2.8

Dockerfile

@@ -1,4 +1,4 @@
-FROM oven/bun:1.2.2-alpine AS base
+FROM oven/bun:1.2.8-alpine AS base
 LABEL org.opencontainers.image.source="https://github.com/C4illin/ConvertX"
 WORKDIR /app