update AZSDK1001 to replace the value with a base64 one (#8330)

Author: scbedd

tools/test-proxy/Azure.Sdk.Tools.TestProxy/Common/SanitizerDictionary.cs

@@ -75,7 +75,7 @@ public SanitizerDictionary() {
                     "AZSDK1000"
                 ),
                 new RegisteredSanitizer(
-                    new GeneralRegexSanitizer(regex: "AccountKey=(?<key>[^;\\\"]+)", groupForReplace: "key"),
+                    new GeneralRegexSanitizer(regex: "AccountKey=(?<key>[^;\\\"]+)", value: BASE64ZERO, groupForReplace: "key"),
                     "AZSDK1001"
                 ),
                 new RegisteredSanitizer(