Don't emit Ruby warnings when requiring opensearch-dsl

[Earlopain]

Description

The removed define_method in options.rb just ensured that you are able to use source and _source, that's all this does. The other entries where this isn't a problem are simply overwritten, as you can see from the warnings. Just switch to handwriting this one special case.

The second change removes a option_method :max_expansions from match.rb. This previously appeared twice in the list and also caused a warning.

$ RUBYOPT=-w bundle exec irb
irb(main):001> require "opensearch-dsl"
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old fields
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of fields was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old script_fields
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of script_fields was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old fielddata_fields
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of fielddata_fields was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old rescore
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of rescore was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old explain
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of explain was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old version
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of version was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old indices_boost
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of indices_boost was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old track_scores
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of track_scores was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old min_score
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of min_score was here
opensearch-ruby/lib/opensearch/dsl/search/options.rb:59: warning: method redefined; discarding old track_total_hits
opensearch-ruby/lib/opensearch/dsl/search/options.rb:55: warning: previous definition of track_total_hits was here
opensearch-ruby/lib/opensearch/dsl/search/base_component.rb:75: warning: method redefined; discarding old max_expansions
opensearch-ruby/lib/opensearch/dsl/search/base_component.rb:75: warning: previous definition of max_expansions was here
=> true

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[nhtruong]

Woah. Nice catches! Thank you!!