Revert "Support for stmtListExpr in parser after major keywords. Scaled down version. (#10852)"

This reverts commit 862897dc0f.

tests/parser/tstmtlist_expr.nim

@@ -1,20 +0,0 @@
-discard """
-  output: '''10'''
-"""
-
-proc xx(a: int): int =
-  let y = 0
-  return
-    var x = 0
-    x + y
-
-proc b(x: int): int = 
-  raise 
-    var e: ref Exception
-    new(e)
-    e.msg = "My Exception msg"
-    e
-
-##issue 4035
-echo(5 +
-5)