Bump regex from 1.7.1 to 1.7.3 (#883)

Bumps [regex](https://github.com/rust-lang/regex) from 1.7.1 to 1.7.3.
- [Release notes](https://github.com/rust-lang/regex/releases)
- [Changelog](https://github.com/rust-lang/regex/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/regex/compare/1.7.1...1.7.3)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

testing/integration-tests/Cargo.toml

@@ -21,7 +21,7 @@ codec = { package = "parity-scale-codec", version = "3.0.0", default-features =
 frame-metadata = "15.0.0"
 futures = "0.3.27"
 hex = "0.4.3"
-regex = "1.5.0"
+regex = "1.7.3"
 scale-info = { version = "2.4.0", features = ["bit-vec"] }
 sp-core = { version = "18.0.0", default-features = false }
 sp-runtime = "20.0.0"