Fix tribute related bug

[SleeplessOne1917]

Description

A recent change caused the frontend build to crash with this error:

lemmy-ui-1  | Node.js v20.16.0
lemmy-ui-1  | /app/node_modules/.pnpm/[email protected]/node_modules/tributejs/dist/tribute.js:98
lemmy-ui-1  |   if (window && typeof window.CustomEvent !== "function") {
lemmy-ui-1  |   ^
lemmy-ui-1  | 
lemmy-ui-1  | ReferenceError: window is not defined
lemmy-ui-1  |     at /app/node_modules/.pnpm/[email protected]/node_modules/tributejs/dist/tribute.js:98:3
lemmy-ui-1  |     at /app/node_modules/.pnpm/[email protected]/node_modules/tributejs/dist/tribute.js:2:83
lemmy-ui-1  |     at Object.<anonymous> (/app/node_modules/.pnpm/[email protected]/node_modules/tributejs/dist/tribute.js:5:2)
lemmy-ui-1  |     at Module._compile (node:internal/modules/cjs/loader:1358:14)
lemmy-ui-1  |     at Module._extensions..js (node:internal/modules/cjs/loader:1416:10)
lemmy-ui-1  |     at Module.load (node:internal/modules/cjs/loader:1208:32)
lemmy-ui-1  |     at Module._load (node:internal/modules/cjs/loader:1024:12)
lemmy-ui-1  |     at Module.require (node:internal/modules/cjs/loader:1233:19)
lemmy-ui-1  |     at require (node:internal/modules/helpers:179:18)
lemmy-ui-1  |     at Object.tributejs (/app/dist/js/server.js:4103:18)

This change fixes the issue by only importing tributejs when the app is being run in the browser.

[dessalines]

This one is causing the error.

[SleeplessOne1917]

I was able to run the app just fine after making the change to markdown.ts.

Edit: This caused an unrelated error to the one I'm fixing. I rolled it back to 0.19.4.

[dessalines]

We might just need to add an exception for the require rule, because I don't see any other way around it. Tribute should be smart enough to null check the window object for SSR apps, but it doesn't.