- remove tests already thoroughly covered in unit tests
- #3139 part 2 of 3
- make checks of `<form>` tag helper more consistent with others
- use a tag helper initializer but testing every variant; covered in unit tests
- remove `MvcStartupTest` and associated web site
- scenario covered elsewhere
- remove `PrecompilationTest.PrecompiledView_RendersCorrectly()`
- scenario covered elsewhere and shouldn't do I/O on checked-in files
c8c0c5303e