fix(sdmx_series_ecb_dwa): refresh content digest after key strip

sdmx_series_ecb_dwa/meta.json

@@ -51,8 +51,8 @@
   "build": {
     "built_at": "2026-06-18T22:30:16.365013Z",
     "parsimony_version": null,
-    "builder": null,
-    "content_sha256": "e4ddd7f068c728d2cd69924eea61f41c1f4b0f43fb5020a98003f2c13464ef37",
+    "builder": "strip-ecb-flow-prefix-keys",
+    "content_sha256": "3f98d69451d7acb34a74e562e5ea020ecc160d2766abb21eefb52a49ff0c8d45",
     "manifest_contract_sha256": "e12235ce7b6f3a7d8269f304544f34ba977d9dfb63d505ccd3b5b8a63d1c6c22"
   }
 }