Add folder exclusions to randomPage script (#75)

* Fix: exclude `/contributing/` from randomPage

Credit to Descawed on MMC Discord for the fix:

- [1](https://discord.com/channels/210394599246659585/1243854227605028866/1270656132318232639)
- [2](https://discord.com/channels/210394599246659585/1243854227605028866/1270697825201557505)

Author: MasssiveJuice08

quartz/components/scripts/randomPage.inline.ts

@@ -4,18 +4,19 @@ function getRandomInt(max: number) {
     return Math.floor(Math.random() * max);
   }
 
+function isValidUrl(newSlug: string, oldSlug: String) {
+  return oldSlug !== newSlug && !newSlug.includes("/contributing/")
+}
+
 async function navigateToRandomPage() {
     const fullSlug = getFullSlug(window)
     const data = await fetchData
     const allPosts = Object.keys(data).map((slug) => simplifySlug(slug as FullSlug))
     // window.location.href = `${pathToRoot(fullSlug)}/${allPosts[getRandomInt(allPosts.length - 1)]}`
     let newSlug = `${pathToRoot(fullSlug)}/${allPosts[getRandomInt(allPosts.length - 1)]}`;
 
-    if (newSlug === fullSlug) {
-      // Generate a new random slug until it's different from the starting fullSlug
-      do {
-        newSlug = `${pathToRoot(fullSlug)}/${allPosts[getRandomInt(allPosts.length - 1)]}`;
-      } while (newSlug === fullSlug);
+    while (!isValidUrl(newSlug, fullSlug)) {
+      newSlug = `${pathToRoot(fullSlug)}/${allPosts[getRandomInt(allPosts.length - 1)]}`;
     }
     window.location.href = newSlug;
 }