llm policy: link to "detective" section (#1090)

Author: tshepang

src/policies/llm-usage.md

@@ -11,7 +11,7 @@ and we do not allow them to be used in ways that risk losing our shared social a
 nor in ways that hurt our goals of creating a strong community.
 
 We are aware that many clauses in this policy are unenforceable.
-Our goal is *not* to catch every violation (see "It's not your job to play detective", below).
+Our goal is *not* to catch every violation (see [It's not your job to play detective](#its-not-your-job-to-play-detective), below).
 Instead, our goal is to remove plausible deniability: to force a choice between following the policy and intentionally violating it.
 See [Money laundering and AML compliance](https://www.bitsaboutmoney.com/archive/money-laundering-and-aml-compliance/) for more background about the motivation.