Rollup merge of #154430 - apiraino:create-gpu-target-notif-group, r=jieyouxu

Create GPU target notification group

Creating the notification group for the newly created GPU target (see [mcp#960](https://rust-lang.zulipchat.com/#narrow/channel/233931-t-compiler.2Fmajor-changes/topic/Create.20a.20GPU.20notification.20group.20compiler-team.23960/near/568629680))

I'm following these [steps](#133334).

(feel free to suggest a better wording)

r? @jieyouxu

Author: jhpratt

triagebot.toml

@@ -194,6 +194,11 @@ Hi relnotes-interest-group, this issue/PR could use some help in reviewing /
 adjusting release notes. Could you take a look if available? Thanks <3
 """
 
+[ping.gpu-target]
+message = """\
+Hi GPU experts, this issue/PR could use some guidance on how this should be
+resolved/implemented. Could you take a look if available? Thanks <3
+"""
 
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