build: Update lerna to 7.1.1

[mydea]

We've been on an alpha version before, so it makes sense to update to the latest stable version instead. There are some removed things that we are not using, so updating should just fix some bugs and not much else.

I ran yarn lerna repair to clean up config.

See: https://github.com/lerna/lerna/releases/tag/7.0.0

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	21.78 KB (0%)
@sentry/browser - ES5 CDN Bundle (minified)	68.44 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	20.09 KB (+0.01% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	59.72 KB (0%)
@sentry/browser - Webpack (gzipped + minified)	21.69 KB (0%)
@sentry/browser - Webpack (minified)	70.83 KB (0%)
@sentry/react - Webpack (gzipped + minified)	21.72 KB (0%)
@sentry/nextjs Client - Webpack (gzipped + minified)	50.1 KB (-0.35% 🔽)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	29.64 KB (-0.43% 🔽)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	27.72 KB (-0.41% 🔽)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	49.43 KB (0%)
@sentry/replay - Webpack (gzipped + minified)	43.12 KB (0%)
@sentry/browser + @sentry/tracing + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	69.08 KB (-0.21% 🔽)
@sentry/browser + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	61.65 KB (+0.01% 🔺)