Tests: remove unreliable syntax test

test/feature/syntax.vader

@@ -1,24 +0,0 @@
-Before:
-  Startify
-  doautocmd CursorMoved
-
-Execute (Between brackets -> StartifyNumber):
-  AssertEqual 'StartifyNumber', SyntaxAt()
-
-Execute (Brackets -> StartifyBracket):
-  AssertEqual 'StartifyBracket', SyntaxAt(3)
-
-Execute (First entry -> StartifySpecial):
-  AssertEqual 'StartifySpecial', SyntaxAt(9)
-
-Execute (Section header -> StartifySection):
-  normal! 2j
-  AssertEqual 'StartifySection', SyntaxAt(4)
-
-Execute (Second entry (separator) -> StartifySlash):
-  normal! 4j
-  AssertEqual 'StartifySlash', SyntaxAt(9)
-
-Execute (Third entry (session) -> StartifyFile):
-  normal! 8j
-  AssertEqual 'StartifyFile', SyntaxAt(9)

test/vimrc

@@ -9,6 +9,6 @@ syntax enable
 set hidden
 set sessionoptions-=tabpages
 
-let g:startify_session_dir = 'include'
+let g:startify_session_dir = 'session'
 let g:startify_relative_path = 1
 let g:startify_custom_header = []