Update repository signing certificate (#500)

Author: loic-sharma

src/Validation.PackageSigning.ProcessSignature/Settings/prod.json

@@ -20,7 +20,7 @@
   },
   "ProcessSignature": {
     "AllowedRepositorySigningCertificates": [
-      "cf7ac17ad047ecd5fdc36822031b12d4ef078b6f2b4c5e6ba41f8ff2cf4bad67"
+      "0e5f38f57dc1bcc806d8494f4f90fbcedd988b46760709cbeec6f4219aa6157d"
     ],
     "V3ServiceIndexUrl": "https://api.nuget.org/v3/index.json",
     "CommitRepositorySignatures":  false