patch 8.1.1955: tests contain typos

Problem:    Tests contain typos.
Solution:   Correct the typos. (Dominique Pelle)
diff --git a/src/testdir/test_tcl.vim b/src/testdir/test_tcl.vim
index 9923a2e..c2fd191 100644
--- a/src/testdir/test_tcl.vim
+++ b/src/testdir/test_tcl.vim
@@ -4,7 +4,7 @@
 CheckFeature tcl
 
 " Helper function as there is no builtin tcleval() function similar
-" to perleval, luaevel(), pyeval(), etc.
+" to perleval, luaeval(), pyeval(), etc.
 func TclEval(tcl_expr)
   let s = split(execute('tcl ' . a:tcl_expr), "\n")
   return (len(s) == 0) ? '' : s[-1]