kvcoord: add Transport.Reset()

[erikgrinaker]

Extracted from #118943.

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This resets the transport back to the first replica in the list.

Epic: none
Release note: None

[cockroach-teamcity]

This change is 

[nvanbenschoten]

Reviewed 6 of 6 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @andrewbaptist and @erikgrinaker)

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pkg/kv/kvclient/kvcoord/transport_test.go line 134 at r1 (raw file):

	gt.SkipReplica()
	require.True(t, gt.IsExhausted())
	gt.Reset()

nit: Want to add in a require.False(t, gt.IsExhausted()) after this?

[erikgrinaker]

bors r+

Reviewable status: complete! 0 of 0 LGTMs obtained (and 1 stale) (waiting on @andrewbaptist and @nvanbenschoten)

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pkg/kv/kvclient/kvcoord/transport_test.go line 134 at r1 (raw file):

Previously, nvanbenschoten (Nathan VanBenschoten) wrote…

nit: Want to add in a require.False(t, gt.IsExhausted()) after this?

Yep, good call, done.

[erikgrinaker]

erikgrinaker requested a review from nvanbenschoten now

Sigh, Reviewable keeps doing this. I thought unchecking "Sync requested reviewers" was the thing to do, but maybe it actually needs to be checked.

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)