fix(sdmx_series_ecb_tgb): refresh content digest after key strip

sdmx_series_ecb_tgb/meta.json

@@ -42,8 +42,8 @@
   "build": {
     "built_at": "2026-06-18T22:35:27.281919Z",
     "parsimony_version": null,
-    "builder": null,
-    "content_sha256": "f53a2b7a5c85c80a7ecd9b469fd37631268225438914dab75f7146badc9b6071",
+    "builder": "strip-ecb-flow-prefix-keys",
+    "content_sha256": "1e4bf1e70296acfb1254bd2e6af75f11a46bef85e45db4eee320b72d4b4515fc",
     "manifest_contract_sha256": "ff285350c4111d77a58da56912afda0347f0842608829cf8da3275602361b459"
   }
 }