gtr-search-bar.c: changed the 'active' attribute of the function at line 701 to "changed".

gtr-tab.c: removed the declaration and use of the msg_grab_focus function

Currently, to search something on in a file using the search bar, the user has to: 1_Enter the search key 2_Press enter for the query to take place

But we want the query to take effect as the user types. so these changes I made implemented this solution