Bump go.unistack.org/micro/v3 from 3.8.14 to 3.8.15

Bumps [go.unistack.org/micro/v3](https://github.com/unistack-org/micro) from 3.8.14 to 3.8.15.
- [Release notes](https://github.com/unistack-org/micro/releases)
- [Commits](https://github.com/unistack-org/micro/compare/v3.8.14...v3.8.15)

---
updated-dependencies:
- dependency-name: go.unistack.org/micro/v3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

go.mod

@@ -4,6 +4,6 @@ go 1.16
 
 require (
 	github.com/segmentio/encoding v0.3.3
-	go.unistack.org/micro/v3 v3.8.14
+	go.unistack.org/micro/v3 v3.8.15
 	google.golang.org/protobuf v1.27.1
 )