Add note about liquidation risk in staking-strategies section

[vercel[bot]]

This pull request is being automatically deployed with Vercel (learn more).
To see the status of your deployment, click below or on the icon next to each commit.

🔍 Inspect: https://vercel.com/michaelcohen716/synthetix-community/6tsa16vci
✅ Preview: https://synthetix-comm-git-fork-coventry-staking-strategy-liqu-f332c2.michaelcohen716.now.sh

[michaelcohen716]

@coventry i think you mean to bring their ratio back above **500%**

[coventry]

@michaelcohen716 , thanks. PTAL, I've updated it.