Optimize Hash methods with Kernel#hash

[k0kubun]

rb_obj_hash is leaf. You don't need to push a frame when you dispatch that method.

before: ruby 3.4.0dev (2024-03-01T18:03:00Z master 661f9e6d03) [x86_64-linux]
after: ruby 3.4.0dev (2024-03-01T18:22:33Z kernel-hash 7b226d427c) [x86_64-linux]
Calculating -------------------------------------
                         before       after
      hash.key?(obj)    40.595M     58.930M i/s -     30.000M times in 0.739008s 0.509077s

Comparison:
                   hash.key?(obj)
               after:  58930238.8 i/s
              before:  40594941.2 i/s - 1.45x  slower

This seems to speed up railsbench:

before: ruby 3.4.0dev (2024-03-01T18:03:00Z master 661f9e6d03) [x86_64-linux]
after: ruby 3.4.0dev (2024-03-01T18:22:33Z kernel-hash 7b226d427c) [x86_64-linux]

----------  -----------  ----------  ----------  ----------  -------------  ------------
bench       before (ms)  stddev (%)  after (ms)  stddev (%)  after 1st itr  before/after
railsbench  4241.8       0.5         4213.9      0.4         1.01           1.01
----------  -----------  ----------  ----------  ----------  -------------  ------------

before: ruby 3.4.0dev (2024-03-01T18:03:00Z master 661f9e6d03) +YJIT [x86_64-linux]
after: ruby 3.4.0dev (2024-03-01T18:22:33Z kernel-hash 7b226d427c) +YJIT [x86_64-linux]

----------  -----------  ----------  ----------  ----------  -------------  ------------
bench       before (ms)  stddev (%)  after (ms)  stddev (%)  after 1st itr  before/after
railsbench  2443.5       0.8         2405.8      0.8         0.99           1.02
----------  -----------  ----------  ----------  ----------  -------------  ------------