Update 3.15-rc to 3.15.0a4

Author: docker-library-bot

3.15-rc/alpine3.22/Dockerfile

@@ -98,10 +98,10 @@
   "3.15-rc": {
     "checksums": {
       "source": {
-        "sha256": "6ab02cdac24505779877bb1d9189432d67e90ddf2a9b8b7b373ead54ac07b607"
+        "sha256": "a0a521d5c480b89979da1aefce29750eb158128c0178728ebfef7511c21b4e77"
       },
       "windows": {
-        "sha256": "05d0a8932ca359e349571b193858be1af72a3cff086bfe08cbe6d1e2140726c9"
+        "sha256": "4dff016067a5e4888fb49666750f0f1a71f4924e4bc41abe66bd2e966f7fc9d3"
       }
     },
     "variants": [
@@ -114,6 +114,6 @@
       "windows/windowsservercore-ltsc2025",
       "windows/windowsservercore-ltsc2022"
     ],
-    "version": "3.15.0a3"
+    "version": "3.15.0a4"
   }
 }