ci: Improve canary issue creation

[mydea]

1. Do not create an issue when manually running canary tests
2. Update existing issue instead of creating a new one every time
3. Update issue name so we see which canary test is failing

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	21.05 KB (+0.13% 🔺)
@sentry/browser - ES5 CDN Bundle (minified)	65.69 KB (+0.1% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	19.59 KB (+0.13% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	58.16 KB (+0.14% 🔺)
@sentry/browser - Webpack (gzipped + minified)	21.21 KB (+0.18% 🔺)
@sentry/browser - Webpack (minified)	69.08 KB (+0.06% 🔺)
@sentry/react - Webpack (gzipped + minified)	21.23 KB (+0.19% 🔺)
@sentry/nextjs Client - Webpack (gzipped + minified)	49.16 KB (+0.1% 🔺)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	28.67 KB (+0.11% 🔺)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	26.91 KB (+0.11% 🔺)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	48.49 KB (+1.85% 🔺)
@sentry/replay - Webpack (gzipped + minified)	42.17 KB (+1.71% 🔺)
@sentry/browser + @sentry/tracing + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	67.48 KB (+1.47% 🔺)
@sentry/browser + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	60.37 KB (+1.67% 🔺)