* docs(components): [select] create example using 'value-key' attribute
Example using option type with same value of 'label' property
- Use 'id' property of option as value of 'value-key' attribute
* docs(docs): apply 'value-key' example to 'select.md'
Remove the existing 'tip' and add it to the description
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Co-authored-by: FE_강명구 <mg_@ex-em.com>
