patch 9.0.0607: verbose echo message test fails on Mac OS

Problem:    Verbose echo message test fails on Mac OS.
Solution:   Skip the test on Mac OS.
diff --git a/src/testdir/check.vim b/src/testdir/check.vim
index c3f2563..82abb64 100644
--- a/src/testdir/check.vim
+++ b/src/testdir/check.vim
@@ -111,6 +111,14 @@
   endif
 endfunc
 
+" Command to check for not running on a MacOS
+command CheckNotMac call CheckNotMac()
+func CheckNotMac()
+  if has('mac')
+    throw 'Skipped: does not work on MacOS'
+  endif
+endfunc
+
 " Command to check for not running on a MacOS M1 system.
 command CheckNotMacM1 call CheckNotMacM1()
 func CheckNotMacM1()