patch 8.2.0156: various typos in source files and tests

Problem:    Various typos in source files and tests.
Solution:   Fix the typos. (Emir Sari, closes #5532)
diff --git a/src/testdir/test_netbeans.vim b/src/testdir/test_netbeans.vim
index 690ac67..61da44d 100644
--- a/src/testdir/test_netbeans.vim
+++ b/src/testdir/test_netbeans.vim
@@ -10,7 +10,7 @@
   throw 'Skipped: python program missing'
 endif
 
-" Run "testfunc" after sarting the server and stop the server afterwards.
+" Run "testfunc" after starting the server and stop the server afterwards.
 func s:run_server(testfunc, ...)
   call RunServer('test_netbeans.py', a:testfunc, a:000)
 endfunc