fix: create more comprehensive field row labels#9458

microbit-robert wants to merge 1 commit intoRaspberryPiFoundation:add-screen-reader-support-experimentalRaspberryPiFoundation/blockly:add-screen-reader-support-experimentalfrom

microbit-matt-hillsdon:field-row-labelmicrobit-matt-hillsdon/blockly:field-row-labelCopy head branch name to clipboard