fix(ci): use alpine:3.18.12

Signed-off-by: Cocoa <i@uwucocoa.moe>

Author: cocoa-xu

.github/workflows/linux-precompile-musl.yml

@@ -12,7 +12,7 @@ concurrency:
 jobs:
   alpine:
     runs-on: ubuntu-latest
-    container: alpine:latest
+    container: alpine:3.18.12
     env:
       MIX_ENV: prod
       OPENCV_VER: "4.11.0"

.github/workflows/linux-x86_64.yml

@@ -68,7 +68,7 @@ concurrency:
 jobs:
   musl:
     runs-on: ubuntu-latest
-    container: alpine:latest
+    container: alpine:3.18.12
     env:
       MIX_ENV: test
       OPENCV_VER: "4.11.0"