HybridCache support for Tuples

[mrazvanalex]

Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

I've been trying to implement a system based on eTag to return a 304 in case the existing resource has not changed in the Database.

I have a HybridCache instance working alongside this ETag in the API layer. When returning a tuple ( obj, string ) from the cache, they are returned as null, even if values are attributed in the service call. Provided sample code:

var tags = new List<string> { "test" };
var entryOptions = new HybridCacheEntryOptions
{
    Expiration = TimeSpan.FromMinutes(1),
    LocalCacheExpiration = TimeSpan.FromMinutes(1)
};

var clientETag = httpContext.Request.Headers["If-None-Match"].FirstOrDefault();
var  (result, eTag) = await _cache.GetOrCreateAsync($"identifier", async get =>
{
    var (result, eTag) = await _companyService.GetPaginatedBillsAasync(companyId, filter, clientETag); // values retrieved from service 
    return  (result, eTag); // values are attributed.
}, entryOptions, tags); // values are still shown in breakpoints
// After reaching this point, result and eTag are now null.

if (result == null) // Here result is always null. 
{
    return Results.StatusCode(304); 
}

Describe the solution you'd like

I expect the tuple to retain it's value after the Func has finished it's execution.

Additional context