[m-rev.] for review: announce the recent fix for string switches

[Julien Fischer]

Announce the recent fix for string switches.

NEWS:
     As above.

diff --git a/NEWS b/NEWS
index 7e49bfd..0d8b54a 100644
--- a/NEWS
+++ b/NEWS
@@ -957,6 +957,9 @@ This is a bug-fix release.
  * We have fixed a bug that was causing invalid fact table file names
    to be written to dependency files.

+* We have fixed a bug that was causing the MLDS backend to incorrectly
+  reject some switches on strings.
+
  NEWS for Mercury 22.01.4
  ========================