Update contributing URL to point to a "welcome" discussion (#190)

Author: StevenClontz

packages/viewer/src/constants.ts

@@ -18,7 +18,7 @@ export const build = {
 
 export const bundleSse = VITE_BUNDLE_SSE === 'true'
 
-export const contributingUrl = `https://github.com/pi-base/data/wiki/Contributing`
+export const contributingUrl = `https://github.com/orgs/pi-base/discussions/880`
 export const helpUrl = `https://github.com/pi-base/data/wiki/`
 export const sentryIngest =
   'https://[email protected]/5251960'