Bug 33406: Filter out some known isolated trouble makers

Test plan:
1) Launch k-t-d with ES:
-- ktd --es7 pull
-- ktd --es7 up
2) Visit /cgi-bin/koha/authorities/authorities-home.pl and search for 'tim'
3) Edit that, add a dash '-' to 100$a, like 'Bunce, Tim - name'"
4) Do a authority search for 'tim - name', notice it errors out
5) Apply patch
6) Perform the same search, notice it doesn't error and returns the correct record

Signed-off-by: Pedro Amorim <pedro.amorim@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 27c6171222)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>

Koha/SearchEngine/Elasticsearch/QueryBuilder.pm

@@ -1236,6 +1236,9 @@ sub _split_query {
     # Filter out empty values
     @tokens = grep( /\S/, @tokens );
 
+    # Filter out some known isolated trouble makers: -, ^, \, ~, +
+    @tokens = grep( !/^[-\^\\~\+]*$/, @tokens );
+
     return @tokens;
 }