Bump steep from 1.9.3 to 1.9.4 in /steep

Bumps [steep](https://github.com/soutaro/steep) from 1.9.3 to 1.9.4.
- [Release notes](https://github.com/soutaro/steep/releases)
- [Changelog](https://github.com/soutaro/steep/blob/master/CHANGELOG.md)
- [Commits](soutaro/steep@v1.9.3...v1.9.4)

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

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

Author: dependabot[bot]

steep/Gemfile

@@ -1,4 +1,4 @@
 source "https://rubygems.org"
 
 gem "rbs", "~> 3.8.1"
-gem "steep", "~> 1.9.2"
+gem "steep", "~> 1.9.4"

steep/Gemfile.lock

@@ -44,7 +44,7 @@ GEM
     rbs (3.8.1)
       logger
     securerandom (0.4.1)
-    steep (1.9.3)
+    steep (1.9.4)
       activesupport (>= 5.1)
       concurrent-ruby (>= 1.1.10)
       csv (>= 3.0.9)
@@ -73,7 +73,7 @@ PLATFORMS
 
 DEPENDENCIES
   rbs (~> 3.8.1)
-  steep (~> 1.9.2)
+  steep (~> 1.9.4)
 
 BUNDLED WITH
    2.5.16