Implement IEquatable<T> on the runtime handle types.

[teo-tsirpanis]

I also called the Equals method via the interface in the tests.

Fixes Contributes to #62944.

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, to please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

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Issue Details

---

I also called the Equals method via the interface in the tests.

Fixes Contributes to #62944.

Author:	teo-tsirpanis
Assignees:	-
Labels:	area-System.Runtime, new-api-needs-documentation, community-contribution
Milestone:	-

[jkotas]

You should be also able delete these baseline exclusions: https://github.com/dotnet/runtime/blob/main/src/libraries/System.Runtime/src/MatchingRefApiCompatBaseline.txt#L28

[jkotas]

Thank you