Merge bitcoin/bitcoin#27072: doc: Remove unused REVIEWERS file

fa8e3aa60d doc: Remove unused REVIEWERS file (721217.xyz)

Pull request description:

  Unused for way more than two months after https://github.com/bitcoin/bitcoin/pull/25613#issuecomment-1200113115

  See also bb5ebadeaa

ACKs for top commit:
  sipa:
    ACK fa8e3aa60d
  john-moffett:
    ACK fa8e3aa60d

Tree-SHA512: def650d34f04abd18e37cf19b5df34463157a99fbb537c4c98092c8312eb2a572ccde13ec5374f3b9e7cb90cef220cfe07f4522ffbfeb9407b20b3ada1d7706c

REVIEWERS

@@ -1,17 +0,0 @@
-# ==============================================================================
-#                          Bitcoin Core REVIEWERS
-# ==============================================================================
-
-# Configuration of automated review requests for the bitcoin/bitcoin repo
-# via DrahtBot.
-
-# Order is not important; if a modified file or directory matches a fnmatch,
-# the reviewer will be mentioned in a PR comment requesting a review.
-
-# Regular contributors are free to add their names to specific directories or
-# files provided that they are willing to provide a review.
-
-# Absence from this list should not be interpreted as a discouragement to
-# review a pull request. Peer review is always welcome and is a critical
-# component of the progress of the codebase. Information on peer review
-# guidelines can be found in the CONTRIBUTING.md doc.