vim-patch:8.1.1483: skipped tests are not properly listed

Problem:    Skipped tests are not properly listed.
Solution:   Throw a "Skipped" exception instead of using ":finish" or ":return".
5d30ff1964

Skips quite some (N/A) tests.

vim-patch:8.1.0503: missing change to diff test (included in cf1ffa916)

src/nvim/testdir/test_breakindent.vim

@@ -5,7 +5,7 @@
 " It helps to change the tabstop setting and force a redraw (e.g. see
 " Test_breakindent08())
 if !exists('+breakindent')
-  finish
+  throw 'Skipped: breakindent option not supported'
 endif
 
 source view_util.vim