chore(ci): Add env vars to 404-linter action

[chargome]

With #13083 DSN env vars are now required for prod builds, which is why the linter actions fails.

Since we do not require Sentry in this action we can just pass a placeholder value.

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
develop-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 22, 2025 8:21pm
sentry-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 22, 2025 8:21pm

1 Skipped Deployment

Name	Status	Preview	Comments	Updated (UTC)
changelog	⬜️ Ignored (Inspect)			Mar 22, 2025 8:21pm

[codecov]

Bundle Report

Changes will decrease total bundle size by 15 bytes (-0.0%) ⬇️. This is within the configured threshold ✅

Detailed changes

Bundle name	Size	Change
sentry-docs-server-cjs	10.59MB	-9 bytes (-0.0%) ⬇️
sentry-docs-client-array-push	9.43MB	-6 bytes (-0.0%) ⬇️

Affected Assets, Files, and Routes:

view changes for bundle: sentry-docs-server-cjs

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
1729.js	-3 bytes	1.58MB	-0.0%
../instrumentation.js	-3 bytes	907.85kB	-0.0%
9523.js	-3 bytes	883.91kB	-0.0%

view changes for bundle: sentry-docs-client-array-push

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
static/chunks/pages/_app-*.js	-3 bytes	869.05kB	-0.0%
static/chunks/3464-*.js	-3 bytes	394.39kB	-0.0%
static/WACeTonbtfrQYy57EVOCD/_buildManifest.js (New)	578 bytes	578 bytes	100.0% 🚀
static/WACeTonbtfrQYy57EVOCD/_ssgManifest.js (New)	77 bytes	77 bytes	100.0% 🚀
static/lhMYwKv2B4K_hw_f9PDST/_buildManifest.js (Deleted)	-578 bytes	0 bytes	-100.0% 🗑️
static/lhMYwKv2B4K_hw_f9PDST/_ssgManifest.js (Deleted)	-77 bytes	0 bytes	-100.0% 🗑️