patch 8.2.2160: various typos

Problem:    Various typos.
Solution:   Fix spelling mistakes. (closes #7494)
diff --git a/src/testdir/test_terminal3.vim b/src/testdir/test_terminal3.vim
index db6ebc0..75882f1 100644
--- a/src/testdir/test_terminal3.vim
+++ b/src/testdir/test_terminal3.vim
@@ -145,7 +145,7 @@
   call delete('XtermPopup')
 endfunc
 
-" Check a terminal in popup window uses the default mininum size.
+" Check a terminal in popup window uses the default minimum size.
 func Test_terminal_in_popup_min_size()
   CheckRunVimInTerminal