allow searching for unaccepted requests (#3694)

* let search_msgs() return unaccepted requests

unaccepted chat requests are shown in the chatlist,
it should be returned by search_msgs() an by the other search functions as well.

form the view of the user, the search acts like a filter,
so there is no reason to hide things additionally.

also, the user may remember a word in a chat request,
maybe even an archived one (there is no need to accept a request before archiving)
that one wants to search later on.

* test searching for unaccepted requests

* simplyfy expression; `c.blocked!=1` is also what is used in similar statements

CHANGELOG.md

@@ -7,6 +7,7 @@
 ### Changes
 
 ### Fixes
+- `dc_search_msgs()` returns unaccepted requests #3694
 
 
 ## 1.98.0