fix(export): handle ok-case of bad viz while connected

this was an incomplete fix to #1161

while running qri connect we need to properly handle the context deadline for a missing
viz by ignoring the error.

base/archive/zip.go

@@ -5,6 +5,7 @@ import (
  "bytes"
  "context"
  "encoding/json"
+ "errors"
  "fmt"
  "io"
  "io/ioutil"
@@ -95,7 +96,11 @@ func WriteZip(ctx context.Context, store cafs.Filestore, ds *dataset.Dataset, fo
 
  if ds.Viz.RenderedPath != "" {
  if err = maybeWriteRenderedViz(ctx, store, zw, ds.Viz.RenderedPath); err != nil {
- return err
+ if errors.Is(err, context.DeadlineExceeded) {
+ err = nil
+ } else {
+ return err
+ }
  }
  }
  }