Disable some flaky tests on MacOS

src/NzbDrone.Common.Test/CacheTests/CachedFixture.cs

@@ -84,6 +84,7 @@ namespace NzbDrone.Common.Test.CacheTests
         }
 
         [Test]
+        [Platform(Exclude="MacOsX")]
         public void should_honor_ttl()
         {
             int hitCount = 0;
@@ -105,6 +106,7 @@ namespace NzbDrone.Common.Test.CacheTests
 
         [Test]
         [Retry(3)]
+        [Platform(Exclude="MacOsX")]
         public void should_clear_expired_when_they_expire()
         {
             int hitCount = 0;

src/NzbDrone.Common.Test/TPLTests/DebouncerFixture.cs

@@ -7,6 +7,7 @@ using NzbDrone.Common.TPL;
 namespace NzbDrone.Common.Test.TPLTests
 {
     [TestFixture]
+    [Platform(Exclude="MacOsX")]
     public class DebouncerFixture
     {
         public class Counter
@@ -126,4 +127,4 @@ namespace NzbDrone.Common.Test.TPLTests
             counter.Count.Should().Be(1);
         }
     }
-}
+}

src/NzbDrone.Common.Test/TPLTests/RateLimitServiceFixture.cs

@@ -10,6 +10,7 @@ using FluentAssertions;
 namespace NzbDrone.Common.Test.TPLTests
 {
     [TestFixture]
+    [Platform(Exclude="MacOsX")]
     public class RateLimitServiceFixture : TestBase<RateLimitService>
     {
         private DateTime _epoch;