Bump indexmap from 1.9.2 to 1.9.3

Bumps [indexmap](https://github.com/bluss/indexmap) from 1.9.2 to 1.9.3.
- [Release notes](https://github.com/bluss/indexmap/releases)
- [Changelog](https://github.com/bluss/indexmap/blob/master/RELEASES.md)
- [Commits](indexmap-rs/indexmap@1.9.2...1.9.3)

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

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

Cargo.toml

@@ -22,7 +22,7 @@ selectors = "0.24.0"
 smallvec = "1.10.0"
 tendril = "0.4.3"
 ahash = "0.8"
-indexmap = { version = "1.9.2", optional = true }
+indexmap = { version = "1.9.3", optional = true }
 once_cell = "1.0"
 
 [dependencies.getopts]