vim-patch:8.2.4861: it is not easy to restore saved mappings

Problem:    It is not easy to restore saved mappings.
Solution:   Make mapset() accept a dict argument. (Ernie Rael, closes vim/vim#10295)

51d04d16f2

Co-authored-by: Ernie Rael <errael@raelity.com>

test/functional/vimscript/map_functions_spec.lua

@@ -30,6 +30,7 @@ describe('maparg()', function()
       buffer=0,
       nowait=0,
       mode='n',
+      abbr=0,
       noremap=1,
       lnum=0,
     }
@@ -156,6 +157,7 @@ describe('maparg()', function()
         buffer = 0,
         expr = 0,
         mode = 'n',
+        abbr = 0,
         noremap = 1,
         nowait = 0,
         script = 0,