Bump gopkg.in/yaml.v2 from 2.2.7 to 2.2.8
Bump gopkg.in/yaml.v2 from 2.2.7 to 2.2.8

Bumps [gopkg.in/yaml.v2](https://github.com/go-yaml/yaml) from 2.2.7 to 2.2.8.
- [Release notes](https://github.com/go-yaml/yaml/releases)
- [Commits](https://github.com/go-yaml/yaml/compare/v2.2.7...v2.2.8)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
martin-helmich/prometheus-nginxlog-exporter,martin-helmich/prometheus-nginxlog-exporter,martin-helmich/prometheus-nginxlog-exporter