Deleting branch features/erc-message-tags

[J.P.]

The one patch this branch contains was applied as:

  commit 2205546269bf5af01d766dc38720f71046b08dfa
  Author: Vibhav Pant <vibhavp@gmail.com>
  Date:   Mon Apr 24 11:57:46 2017 +0530
  
      Add support for IRCv3 message tags.
      
      * erc-backend.el:
        erc-response: Add `tags' element.
        Add (erc-parse-tags).
        (erc-parse-server-response): Use (erc-parse-tags) to parse message
        tags (if any), and store them in `erc-resopnse' struct.
      
      * erc.el: (erc-display-message): Expose message tags with text
        properties of the corresponding message line.
  
   lisp/erc/erc-backend.el | 30 +++++++++++++++++++++++++-----
   lisp/erc/erc.el         |  5 ++++-
   2 files changed, 29 insertions(+), 6 deletions(-)

I therefore move that the branch be deleted. If no one objects or beats
me to it, I'll follow through on or around April 2, 2022. Thanks.