Add subrequets integrity tag to ensure visitors wont run malicious code

[simpleanalyticsbot]

If a bad actor was able to break into simple analytics they could change out the latest.js code and run whatever code they want on our visitors browsers. Using SRI tags and versions numbers for the script would mitigate this risk.

[adriaandotcom]

This is already possible: https://docs.simpleanalytics.com/sri