#4454 Clean up more tests and code

* Remove some tests we no longer need
* Delete blocks of redundant code
* Compress some tests together to simplify them
* Remove a little code for ancient linter versions
* Escape more executables we didn't escape before
* Rename a deno option that didn't match our conventions

test/handler/test_ghc_handler.vader

@@ -1,3 +1,6 @@
+After:
+  unlet! g:detail
+
 Execute(The ghc handler should handle hdevtools output):
   call ale#test#SetFilename('foo.hs')