Lock regex crate at min 1.5.5 for CVE-2022-24713

Cargo.lock already specifies 1.5.5, but we should also do it in
Cargo.toml.

Cargo.toml

@@ -63,7 +63,7 @@ clircle = "0.3"
 bugreport = { version = "0.4", optional = true }
 dirs-next = { version = "2.0.0", optional = true }
 grep-cli = { version = "0.1.6", optional = true }
-regex = { version = "1.5", optional = true }
+regex = { version = "1.5.5", optional = true }
 walkdir = { version = "2.0", optional = true }
 bytesize = { version = "1.1.0" }