bug: Fix CSP when using SPACEBIN_ANALYTICS environment variable

[lukewhrit]

Describe the bug

When the SPACEBIN_ANALYTICS variable is populated, the browser will block loading of the URL due to Content Security Policy

To Reproduce

Steps to reproduce the behavior (What were you doing at the time?):

1. Go to https://spacebin-staging.lwhr.xyz (which has the SPACEBIN_ANALYTICS variable setup)
2. Open dev tools
3. Notice Content-Security-Policy: The page’s settings blocked a script (script-src-elem) at https://plausible.lwhr.xyz/js/script.js from being executed because it violates the following directive: “script-src 'self' 'unsafe-inline'” in the console.

Expected behavior

It should load properly and be included into the Content Security Policy.