Fix erroneous SO suffix in darwin64-debug-test-64-clang target

Reviewed-by: Richard Levitte <levitte@openssl.org>

Configurations/90-team.conf

@@ -118,6 +118,6 @@
         shared_target    => "darwin-shared",
         shared_cflag     => "-fPIC -fno-common",
         shared_ldflag    => "-arch x86_64 -dynamiclib",
-        shared_extension => ".so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR).dylib",
+        shared_extension => ".\$(SHLIB_MAJOR).\$(SHLIB_MINOR).dylib",
     },
 );