Update the documentation

[ofthelit]

Describe the bug The docs are not up to date with the latest version.

To Reproduce For example the headers documentation https://github.com/microsoftgraph/msgraph-sdk-dotnet/blob/dev/docs/headers.md

var newObject = graphServiceClient
	.Object
	.Request(new HeaderOption("Etag", etag))
	.Patch(updatedObject);

This example does not work at all and I found out it is now structured like this after looking at the upgrade document:

var newObject = graphServiceClient
	.Request()
        .Header("ConsistencyLevel", "eventual")
	.Patch(updatedObject);

https://github.com/microsoftgraph/msgraph-sdk-dotnet/blob/dev/docs/collections.md The indentation of the examples is a mess.

Expected behavior I expect the documentation an the examples to match the last stable version.