postverta/pv_exec: worktree/manager.go; 10 LoC

Found a possible issue in [postverta/pv_exec](https://www.github.com/postverta/pv_exec) at [worktree/manager.go](https://github.com/postverta/pv_exec/blob/64d722c27872e25d18562fe7d60304e166bfd390/worktree/manager.go#L83-L92)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first issue it finds, so please do not limit your consideration to the contents of the below message.

> reference to blob is reassigned at line 90

[Click here to see the code in its original context.](https://github.com/postverta/pv_exec/blob/64d722c27872e25d18562fe7d60304e166bfd390/worktree/manager.go#L83-L92)

Click here to show the 10 line(s) of Go which triggered the analyzer.

```go
for _, blob := range listBlobResponse.Blobs {
if blob.Snapshot.IsZero() {
// not a snapshot
continue
}
if blob.Snapshot.After(latest) {
latest = blob.Snapshot
blobRef = &blob
}
}

```

Leave a reaction on this issue to contribute to the project by classifying this instance as a **Bug** :-1:, **Mitigated** :+1:, or **Desirable Behavior** :rocket:
See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: 64d722c27872e25d18562fe7d60304e166bfd390

Inspect worktree/manager.go around lines 83-92 and the linked commit, starting with the analyzer message about the blob reference being reassigned. Determine whether the range-loop reference is a bug, mitigated, or desirable behavior, then record the appropriate classification reaction on the issue.

Written by the indexing model from the issue text.