Add a fluent Validate overload for adding validator types

[89netraM]

Adds a Validate overload to the OptionsBuilder that registers an IValidateOptions type that validates the option type.

Closes #115200

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[tarekgh]

Thanks @89netraM!

I added minor comments, LGTM otherwise.

[89netraM]

Thank you @tarekgh! Thank you for the review and comments!

[89netraM]

Would it be a good idea to also update the examples in PACKAGE.md to use the new method instead of the adding IValidateOptions manually?

Changing

// Configuration to validate
builder.Services.Configure<MyConfigOptions>(builder.Configuration.GetSection(
                                        MyConfigOptions.MyConfig));

// OPtions validation through the DI container
builder.Services.AddSingleton<IValidateOptions
                              <MyConfigOptions>, MyConfigValidation>();

to

// Configuration to validate
builder.Services.AddOptions<MyConfigOptions>()
    .Bind(builder.Configuration.GetSection(MyConfigOptions.MyConfig))
    // Validate with custom IValidateOptions
    .Validate<MyConfigValidation>();

[cincuranet]

@89netraM Yes, please.

[cincuranet]

/ba-g Failures are unrelated.

[cincuranet]

@89netraM Thanks for your contribution.

[89netraM]

Thank you all for having me! It's been fun!