pr create: same-repo branch PRs set source.repo, so spindles skip them #16

A pull request created from a branch in the same repository gets "source": {"branch": "<branch>", "repo": "<the same repo DID>"}. In the pull lexicon, source.repo marks a fork, and the tangled.org website leaves it out for branches in the same repository.

Spindles only run pull requests whose source.repo is unset (spindle/tapclient.go, triggerPullRequestPipeline):

if record.Source == nil || record.Source.Repo != nil {
    l.Info("ignoring pull record: not a branch-based pull request")

So pull_request workflows never run for these pull requests, and the spindle logs ignoring pull record: not a branch-based pull request.