rebase: bump github.com/hashicorp/vault/api from 1.8.3 to 1.9.0

Bumps [github.com/hashicorp/vault/api](https://github.com/hashicorp/vault) from 1.8.3 to 1.9.0.
- [Release notes](https://github.com/hashicorp/vault/releases)
- [Changelog](https://github.com/hashicorp/vault/blob/main/CHANGELOG.md)
- [Commits](https://github.com/hashicorp/vault/compare/v1.8.3...v1.9.0)

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

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

vendor/github.com/armon/go-metrics/.travis.yml

@@ -1,13 +0,0 @@
-language: go
-
-go:
-  - "1.x"
-
-env:
-  - GO111MODULE=on
-
-install:
-  - go get ./...
-
-script:
-  - go test ./...