sql/trim.md: new page

Изменения

Address changes from picodata!943 (merged)

Версия: Picodata 24.3.0-67-g61bc1082 (picodata@61bc1082)

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• Close #233 (closed)
• Changes should be cherry-picked to 24.2: no
• Staging:
  • https://docs.binary.picodata.io/picodata/asabirov_add_trim_md/reference/sql/trim/
  • https://docs.binary.picodata.io/picodata/asabirov_add_trim_md/sql_index/
• See also sbroad#611 (closed)