So long as you include some punctuation between the two its, everything is fine.
Here's an NGram showing that although instances of "it it" have declined steadily since the early 1800s, they remain fairly strong. (The search apparatus ignores intervening commas, semicolons, colons and periods.)
The Y axis shows surprisingly high usage rates, even now.
Conclusion: The "it it" sequence may bother some people, and such fussiness may be causing its decline, but enough people find it useful that it continues on in the language.