[test] Don't run still-crashing compiler_crashers under no-asserts builds.

Per discussion on the list. From now on, when you fix a compiler_crashers
test case, move it to compiler_crashers_fixed so that we get no-asserts and
ASan coverage.

Swift SVN r27055

validation-test/compiler_crashers_fixed/0767-swift-constraints-constraintsystem-solve.swift

@@ -0,0 +1,17 @@
+// RUN: not %target-swift-frontend %s -parse
+
+// Distributed under the terms of the MIT license
+// Test case submitted to project by https://github.com/practicalswift (practicalswift)
+// Test case found by fuzzing
+
+let f = {
+}
+struct A {
+var b {
+let b {
+class func c<h : A.init<T>, y)
+func b.count], f: Hashable> (m: c<()
+let h : b {
+protocol d = [1](")
+protocol A : a {
+func a<d