TEST: remove invalid yield usage from spec example

Using yield outside method definition is invalid, and
with ruby3.3.0dev, this usage in spec example file causes
spec testsuite failure.

So to make test pass also on ruby3.3, remove this usage.

Fixes lsegal#1514 .

Author: mtasaka

spec/handlers/examples/yield_handler_001.rb.txt

@@ -1,7 +1,4 @@
 class Testing
-  # Ignore yields outside methods
-  yield x, y, z
-
   # Should document this
   def mymethod
     yield