en to en_GB translation catalogue (3 entries)

[ctx: Dropdown option label for the custom line height, e.g., "Custom: 1.75".]
en: LINE_HEIGHT_CUSTOM_OPTION_LABEL
en_GB: Custom: %0

[ctx: Dropdown option label for the "Single" line height option.]
en: LINE_HEIGHT_SINGLE_OPTION_LABEL
en_GB: Single

[ctx: Dropdown option label for the "Double" line height option.]
en: LINE_HEIGHT_DOUBLE_OPTION_LABEL
en_GB: Double
