Bump indexmap from 1.7.0 to 1.8.0

Bumps [indexmap](https://github.com/bluss/indexmap) from 1.7.0 to 1.8.0.
- [Release notes](https://github.com/bluss/indexmap/releases)
- [Changelog](https://github.com/bluss/indexmap/blob/master/RELEASES.rst)
- [Commits](indexmap-rs/indexmap@1.7.0...1.8.0)

---
updated-dependencies:
- dependency-name: indexmap
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Cargo.lock

@@ -50,7 +50,7 @@ ci_info = "0.14.3"
 hyperx = "1.4.0"
 attohttpc = { version = "0.18.0", features = ["json"] }
 chain-map = "0.1.0"
-indexmap = "1.7.0"
+indexmap = "1.8.0"
 retry = "1.3.0"
 fs2 = "0.4.3"