Remove SupportedOSPlatformAttribute("windows") from LdapSessionOption

[macsux]

Remove SupportedOSPlatformAttribute("windows") from LdapSessionOptions due to LDAPS now being supported on Linux as of .NET 6. Relevant discussion in issue #60972

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Issue Details

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Remove SupportedOSPlatformAttribute("windows") from LdapSessionOptions due to LDAPS now being supported on Linux as of .NET 6. Relevant discussion in issue #60972

Author:	macsux
Assignees:	-
Labels:	area-System.DirectoryServices, new-api-needs-documentation
Milestone:	-

[macsux]

@buyaa-n I just realized that I opened this PR against main branch. Should I reopen this against v6.0 release branch as this would be a bug fix?

[buyaa-n]

@buyaa-n I just realized that I opened this PR against main branch. Should I reopen this against v6.0 release branch as this would be a bug fix?

1. Every PR goes to the main first, it can be backported to other branches from there
2. I am not sure if this could get approval for servicing in 6.0

[joperezr]

Right, as @buyaa-n suggests let's get this in main first, and then if we think it meets the bar then we can open a backport PR for 6.0 branch and check with servicing if something like this can get approved.

[joperezr]

Added a tiny comment but other than that this looks good, Thanks for fixing!

[macsux]

Since I'm in here, should we add a SupportedOSPlatformAttribute("windows") to VerifyServerCertificate? Seems like it's only implemented under Windows and throws on other implementations since OpenLDAP supports only a handful of preconfigured validation modes rather then offering a callback like Windows API does.

There should be a discussion may be on the linked issue as to whether it makes sense to add something like bool SkipSslCertificateValidation to LdapSessionOptions, but this is an API surface change which I think would require approval to be implemented.

[joperezr]

Do you mind sending a separate PR for that one? I know that it is very related, but what I'm thinking is that we might want to take this specific change into release/6.0 branch (as we are only removing an attribute saying an API is not supported) so it is less of a breaking change than to adding an attribute to an API that claimed to be supported and now say it is not. I understand even without the attribute the API is actually not supported, but it just is a more impacting breaking change, so it will be easier to port just this change into release, than if we have both.

[joperezr]

Sorry it took so long to merge this one, thanks a lot for your contribution @macsux!