Word-wrap liquify mode tooltip

The tooltip was very long, and didn’t fit on the screen. Qt doesn’t automatically word-wrap plaintext tooltips, but wrapping them in <p>…</p> turns them into ‘rich text’ tooltip, which adds automatic word wrapping.

(I’m not sure if this is the ‘canonical’ way of making tooltips word-wrap, but I couldn’t find a better way. Note that the reason I didn’t add the HTML tags inside the string was to avoid a string change, where all the translators would need to retranslate the string (and such wrapping markup doesn’t belong in translatable strings anyway).)

Test Plan

Go to the transform tool. Press the ‘Liquify’ button. Hover over the ‘Mode’ drop-down.

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