Fix the TilWinRT tests (#15820)

It's unknown how this ever worked, or why it stopped working recently.

We removed our desire to directly compare property against T at some point.

(cherry picked from commit 256d46a)
Service-Card-Id: 90625813
Service-Version: 1.18

src/cascadia/UnitTests_TerminalCore/TilWinRtHelpersTests.cpp

@@ -81,23 +81,23 @@ void TilWinRtHelpersTests::TestTruthiness()
     til::property<winrt::hstring> FullString{ L"Full" };
 
     VERIFY_IS_FALSE(Foo());
-    VERIFY_IS_FALSE(Foo);
+    VERIFY_IS_FALSE((bool)Foo);
 
     VERIFY_IS_FALSE(Bar());
-    VERIFY_IS_FALSE(Bar);
+    VERIFY_IS_FALSE((bool)Bar);
 
-    VERIFY_IS_FALSE(EmptyString);
+    VERIFY_IS_FALSE((bool)EmptyString);
     VERIFY_IS_FALSE(!EmptyString().empty());
 
     Foo(true);
     VERIFY_IS_TRUE(Foo());
-    VERIFY_IS_TRUE(Foo);
+    VERIFY_IS_TRUE((bool)Foo);
 
     Bar(11);
     VERIFY_IS_TRUE(Bar());
-    VERIFY_IS_TRUE(Bar);
+    VERIFY_IS_TRUE((bool)Bar);
 
-    VERIFY_IS_TRUE(FullString);
+    VERIFY_IS_TRUE((bool)FullString);
     VERIFY_IS_TRUE(!FullString().empty());
 }
 
@@ -177,13 +177,13 @@ void TilWinRtHelpersTests::TestComposedConstProperties()
     const struct Helper noTouching;
 
     VERIFY_ARE_EQUAL(0, changeMe.Foo());
-    VERIFY_ARE_EQUAL(3, changeMe.Composed().first);
-    VERIFY_ARE_EQUAL(2, changeMe.Composed().second);
+    VERIFY_ARE_EQUAL(3, changeMe.Composed().first());
+    VERIFY_ARE_EQUAL(2, changeMe.Composed().second());
     VERIFY_ARE_EQUAL(L"", changeMe.MyString());
 
     VERIFY_ARE_EQUAL(0, noTouching.Foo());
-    VERIFY_ARE_EQUAL(3, noTouching.Composed().first);
-    VERIFY_ARE_EQUAL(2, noTouching.Composed().second);
+    VERIFY_ARE_EQUAL(3, noTouching.Composed().first());
+    VERIFY_ARE_EQUAL(2, noTouching.Composed().second());
     VERIFY_ARE_EQUAL(L"", noTouching.MyString());
 
     changeMe.Foo(42);

src/inc/til/winrt.h

@@ -21,7 +21,7 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned"
         {
             _value = std::forward<decltype(arg)>(arg);
         }
-        operator bool() const noexcept
+        explicit operator bool() const noexcept
         {
             if constexpr (std::is_same_v<T, winrt::hstring>)
             {