COR's credentials for HTTP Request Operation

Please support credentials: include in CyberChef/src/core/operations/HTTPRequest.mjs. I don't know if would cause issues if it was the default or if it should be an option - but its useful if the COR's site is authenticated.

```
93 });
94
95 const config = {
96 method: method,
97 headers: headers,
98 mode: modeLookup[mode],
+ 99 credentials: "include",
100 cache: "no-cache",
101 };
102
103 if (method !== "GET

```

Start in CyberChef/src/core/operations/HTTPRequest.mjs at the fetch configuration around the headers, mode, and cache settings. Determine whether credentials should always be included or exposed as an option, considering authenticated CORS requests, then verify the HTTP Request operation behaves as intended for authenticated sites.

Written by the indexing model from the issue text.