[elpa] externals/urgrep updated (a357fa4917 -> 6503497188)

[ELPA Syncer]

elpasync pushed a change to branch externals/urgrep.

      from  a357fa4917 Use `ensure-list`
       new  3e91134d87 Simplify argument-checking tests
       new  4eb854c070 Respect buffer-local values of `urgrep-preferred-tools`
       new  0e19d4c981 Don't use `cl-loop`
       new  6503497188 Provide a setter for `urgrep-preferred-tools` to clear 
the cached tool


Summary of changes:
 NEWS.md         |   3 +-
 urgrep-tests.el | 290 +++++++++++++++++++++++++++-----------------------------
 urgrep.el       | 104 ++++++++++----------
 3 files changed, 197 insertions(+), 200 deletions(-)