adding one XFAIL'ed task & actor lifetime test

The `executor_deinit1` test fails 100% of the time
(from what I've seen) so I thought we could track
and see when/if someone happens to fix this bug.

Also, added extra coverage for swiftlang#36298 via `executor_deinit2`

Author: kavon

test/Concurrency/Runtime/executor_deinit1.swift

@@ -0,0 +1,32 @@
+// RUN: %target-run-simple-swift(-parse-as-library -Xfrontend -enable-experimental-concurrency %import-libdispatch) | %FileCheck %s
+
+// REQUIRES: executable_test
+// REQUIRES: concurrency
+// REQUIRES: libdispatch
+
+// FIXME: this should pass! from rdar://73266050
+// XFAIL: *
+
+// doesn't matter that it's bool identity function or not
+func boolIdentityFn(_ x : Bool) -> Bool { return x }
+
+actor FirstActor {
+    func startTest() { // whether startTest is async or sync doesn't matter
+
+        // do not remove this call or if-statement.
+        if boolIdentityFn(true) {}
+
+    }
+
+    deinit() {
+        // CHECK: called deinit
+        print("called deinit")
+    }
+}
+
+@main struct RunIt {
+    static func main() async {
+        let actor = FirstActor()
+        await actor.startTest() // do not remove this call
+    }
+}

test/Concurrency/Runtime/executor_deinit2.swift

@@ -0,0 +1,32 @@
+// RUN: %target-run-simple-swift(-parse-as-library -Xfrontend -enable-experimental-concurrency %import-libdispatch) | %FileCheck %s
+
+// REQUIRES: executable_test
+// REQUIRES: concurrency
+// REQUIRES: libdispatch
+
+// this needs to match with the check count below.
+let NUM_TASKS : Int = 100
+
+final class Capture : ConcurrentValue {
+    func doSomething() { }
+    deinit {
+        // CHECK-COUNT-100: deinit was called!
+        print("deinit was called!")
+    }
+}
+
+@main
+struct App {
+    static func main() async {
+        var n = 0
+        for _ in 1...NUM_TASKS {
+            let c = Capture()
+            let r = Task.runDetached {
+                c.doSomething()
+            }
+            await r.get()
+            n += 1
+        }
+        print("test complete")
+    }
+}