Fix fsnotify repository relocation

FreeBSD CI support

Bumps [github.com/fsnotify/fsnotify](https://github.com/fsnotify/fsnotify) from 1.4.9 to 1.5.1.
- [Release notes](https://github.com/fsnotify/fsnotify/releases)
- [Changelog](https://github.com/fsnotify/fsnotify/blob/master/CHANGELOG.md)
- [Commits](fsnotify/fsnotify@v1.4.9...v1.5.1)

---
updated-dependencies:
- dependency-name: github.com/fsnotify/fsnotify
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* Use temp directory for tests, instead of relative

Since the Go module cache is read-only by default, modifications in the
module directory cause failures for dependents running `go test all`.

* Make test dir cleanup Go 1.14-friendly

* Make test dir cleanup Go 1.11-friendly

Co-authored-by: nxadm <nxadm@users.noreply.github.com>

* Add timeouts to tests

* apparently 30s was too ambitious

* first draft of CompleteLines

* tests

* refactor

* CompleteLines should return the last line if we don't follow

* rename temp dirs to avoid races

* Conditional allocation of strings.Builder

* Fix tests by using the new cleanup()

Co-authored-by: nxadm <nxadm@users.noreply.github.com>

...otherwise we can run into the scenario where: On start we read the contents of the file, we hit EOF, and start watching for changes. But in between the EOF and start watching, the file is updated. But since the watcher wasn't started, we don't notice.

At least on FreeBSD 11.1-STABLE amd64 it fails otherwise...