Revert "add regexp_benchmark target"
Revert "add regexp_benchmark target"

This reverts commit d76eb213ec2644e7e0fde76278b64fb755eae921.

This commits break re2 built with bazel and sandboxing and is
based on an old unmaintained BUILD file for re2.

Change-Id: I287db9a88334aac813bfe537c827214d16954417
Reviewed-on: https://code-review.googlesource.com/4440
Reviewed-by: Paul Wankadia <62d4e38bb1380f055ec4b899baa75e52af09c5f7@google.com>

google/re2,google/re2,google/re2,google/re2,google/re2