From review: remove an extra `\` from the regex pattern. (The regex parser ignores it in front of a `"`, but it's confusing.)
From review: remove an extra `\` from the regex pattern. (The regex parser ignores it in front of a `"`, but it's confusing.)

apple/swift-experimental-string-processing,apple/swift-experimental-string-processing,apple/swift-experimental-string-processing