Auto merge of rust-lang#5580 - matthiaskrgr:regex_dep, r=flip1995

deps: remove unused regex dependency from root crate

changelog: none

Author: bors

Cargo.toml

@@ -31,7 +31,6 @@ path = "src/driver.rs"
 # begin automatic update
 clippy_lints = { version = "0.0.212", path = "clippy_lints" }
 # end automatic update
-regex = "1"
 semver = "0.9"
 rustc_tools_util = { version = "0.2.0", path = "rustc_tools_util"}
 tempfile = { version = "3.1.0", optional = true }