Bump github.com/mackerelio/mackerel-agent from 0.72.14 to 0.73.0

Bumps [github.com/mackerelio/mackerel-agent](https://github.com/mackerelio/mackerel-agent) from 0.72.14 to 0.73.0.
- [Release notes](https://github.com/mackerelio/mackerel-agent/releases)
- [Changelog](https://github.com/mackerelio/mackerel-agent/blob/master/CHANGELOG.md)
- [Commits](mackerelio/mackerel-agent@v0.72.14...v0.73.0)

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

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

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/itchyny/gojq v0.12.8
 	github.com/jpillora/backoff v1.0.0
 	github.com/mackerelio/checkers v0.0.0-20190411030116-60cbd7b55456
-	github.com/mackerelio/mackerel-agent v0.72.14
+	github.com/mackerelio/mackerel-agent v0.73.0
 	github.com/mackerelio/mackerel-client-go v0.21.1
 	github.com/mholt/archiver v3.1.1+incompatible
 	github.com/motemen/go-colorine v0.0.0-20180816141035-45d19169413a