add StreamGroupInfo EntriesRead and Lag

[tvdias]

Fixes #2467

[mgravell]

Suggest also:

• release notes update
• test if possible (if server version is blockage, fine)

[tvdias]

• release notes update

Fixed on 287bacd6c4380a63c75a7b1a0f268e92933b6fde

• test if possible (if server version is blockage, fine)

Fixed on f0f0a1d1c460fb3152f97d71794996e2f6391e4c

[tvdias]

@mgravell I'm getting this same error from https://github.com/StackExchange/StackExchange.Redis/pull/2508/commits/0faf3113c376de36476823e5058a89f414781f0e

[tvdias]

@mgravell this is now ready. the last test that was added (on https://github.com/StackExchange/StackExchange.Redis/pull/2508) looks to be flaky and I had to retry the pipeline a couple of times until it works. also noticed it on the PR itself, that only worked on the 2nd pipeline run, when release notes were updated.

[tvdias]

Hey @mgravell , I think this is ready to go. I'd squash it on merge because I had to create some dummy commits to trigger the build - idk if I could manually do it.

[tvdias]

Hello @mgravell , can you please take a new look on this PR?

And please use the squash it on merge option, as I had created some dummy commits to trigger the builds (idk if I could manually do it).