Fix MaxWorkingSet_GetNotStarted_ThrowsInvalidOperationException

Fixes issue #105422

On MacOS, FreeBSD, SunOS (the ports that share ProcessBSD.c)
the get/set WorkingSet methods only work on the current process.
Skip the parts of tests that operate on other processes.

Remove now redundant MacOS-speicifc tests.

src/libraries/System.Diagnostics.Process/src/System/Diagnostics/Process.BSD.cs

@@ -57,6 +57,8 @@ private static IntPtr ProcessorAffinityCore
         /// </summary>
         private void GetWorkingSetLimits(out IntPtr minWorkingSet, out IntPtr maxWorkingSet)
         {
+            EnsureState(State.HaveNonExitedId);
+
             // We can only do this for the current process on OS X
             if (_processId != Environment.ProcessId)
                 throw new PlatformNotSupportedException(SR.OsxExternalProcessWorkingSetNotSupported);
@@ -86,6 +88,8 @@ private void GetWorkingSetLimits(out IntPtr minWorkingSet, out IntPtr maxWorking
         /// <param name="resultingMax">The resulting maximum working set limit after any changes applied.</param>
         private void SetWorkingSetLimitsCore(IntPtr? newMin, IntPtr? newMax, out IntPtr resultingMin, out IntPtr resultingMax)
         {
+            EnsureState(State.HaveNonExitedId);
+
             // We can only do this for the current process on OS X
             if (_processId != Environment.ProcessId)
                 throw new PlatformNotSupportedException(SR.OsxExternalProcessWorkingSetNotSupported);

src/libraries/System.Diagnostics.Process/src/System/Diagnostics/Process.Linux.cs

@@ -248,6 +248,7 @@ private void GetWorkingSetLimits(out IntPtr minWorkingSet, out IntPtr maxWorking
 #pragma warning disable IDE0060
         private static void SetWorkingSetLimitsCore(IntPtr? newMin, IntPtr? newMax, out IntPtr resultingMin, out IntPtr resultingMax)
         {
+            EnsureState(State.HaveNonExitedId);
             // RLIMIT_RSS with setrlimit not supported on Linux > 2.4.30.
             throw new PlatformNotSupportedException(SR.MinimumWorkingSetNotSupported);
         }

src/libraries/System.Diagnostics.Process/tests/ProcessTests.cs

@@ -603,20 +603,12 @@ public void TestMaxWorkingSet()
         }
 
         [Fact]
-        [SkipOnPlatform(TestPlatforms.OSX | TestPlatforms.FreeBSD | TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS, "Getting MaxWorkingSet is not supported on OSX, BSD, iOS, MacCatalyst, and tvOS.")]
+        [SkipOnPlatform(TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS, "Getting MaxWorkingSet is not supported on iOS, MacCatalyst, and tvOS.")]
         public void MaxWorkingSet_GetNotStarted_ThrowsInvalidOperationException()
         {
             var process = new Process();
             Assert.Throws<InvalidOperationException>(() => process.MaxWorkingSet);
-        }
-
-        [Fact]
-        [PlatformSpecific(TestPlatforms.OSX | TestPlatforms.FreeBSD)]
-        public void MaxValueWorkingSet_GetSetMacos_ThrowsPlatformSupportedException()
-        {
-            var process = new Process();
-            Assert.Throws<PlatformNotSupportedException>(() => process.MaxWorkingSet);
-            Assert.Throws<PlatformNotSupportedException>(() => process.MaxWorkingSet = (IntPtr)1);
+            Assert.Throws<InvalidOperationException>(() => process.MaxWorkingSet = (IntPtr)1);
         }
 
         [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
@@ -659,21 +651,13 @@ public void TestMinWorkingSet()
         }
 
         [Fact]
-        [SkipOnPlatform(TestPlatforms.OSX | TestPlatforms.FreeBSD | TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS, "Getting MinWorkingSet is not supported on OSX, BSD, iOS, MacCatalyst, and tvOS.")]
+        [SkipOnPlatform(TestPlatforms.iOS | TestPlatforms.MacCatalyst | TestPlatforms.tvOS, "Getting MinWorkingSet is not supported on iOS, MacCatalyst, and tvOS.")]
         public void MinWorkingSet_GetNotStarted_ThrowsInvalidOperationException()
         {
             var process = new Process();
             Assert.Throws<InvalidOperationException>(() => process.MinWorkingSet);
         }
 
-        [Fact]
-        [PlatformSpecific(TestPlatforms.OSX | TestPlatforms.FreeBSD)]
-        public void MinWorkingSet_GetMacos_ThrowsPlatformSupportedException()
-        {
-            var process = new Process();
-            Assert.Throws<PlatformNotSupportedException>(() => process.MinWorkingSet);
-        }
-
         [Fact]
         public void TestModules()
         {