Optimize option value detection

[Watson1978]

This patch introduces functions same as rb_hash_has_key()
to reduce rb_funcall() calling because it has a overhead.

−	before	after	result
JSON.parse	302.109k	343.547k	1.14x
JSON.generate	569.705k	568.668k	−

Environment

• MacBook Air (M1, 2020)
• macOS 12.0 beta
• Apple M1
• Ruby 3.0.2

Before

Warming up --------------------------------------
          JSON.parse    30.347k i/100ms
       JSON.generate    56.987k i/100ms
Calculating -------------------------------------
          JSON.parse    302.109k (± 0.2%) i/s -      1.517M in   5.022546s
       JSON.generate    569.705k (± 0.2%) i/s -      2.849M in   5.001462s

After

Warming up --------------------------------------
          JSON.parse    35.109k i/100ms
       JSON.generate    57.611k i/100ms
Calculating -------------------------------------
          JSON.parse    343.547k (± 0.3%) i/s -      1.720M in   5.007637s
       JSON.generate    568.668k (± 0.3%) i/s -      2.881M in   5.065486s

Test code

require 'benchmark/ips'
require 'json'

json =<<-EOF
{
  "$id": "https://example.com/person.schema.json",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "Person",
  "type": "object",
  "properties": {
    "firstName": {
      "type": "string",
      "description": "The person's first name."
    },
    "lastName": {
      "type": "string",
      "description": "The person's last name."
    },
    "age": {
      "description": "Age in years which must be equal to or greater than zero.",
      "type": "integer",
      "minimum": 0
    }
  }
}
EOF

Benchmark.ips do |x|
  x.report('JSON.parse') { JSON.parse(json, symbolize_names: true) }

  data = JSON.parse(json, symbolize_names: true)
  x.report('JSON.generate') { JSON.generate(json, indent: "\t") }
end