Use gh-workflow for tests (take 2) (#41420)

This re-implements the reverted commit 8b051d6cc3.

Closes #ISSUE

Release Notes:

- N/A

---------

Co-authored-by: Ben Kunkle <ben@zed.dev>

script/prettier

@@ -0,0 +1,17 @@
+#!/bin/bash
+set -euxo pipefail
+
+PRETTIER_VERSION=3.5.0
+
+pnpm dlx "prettier@${PRETTIER_VERSION}" assets/settings/default.json --check || {
+    echo "To fix, run from the root of the Zed repo:"
+    echo "  pnpm dlx prettier@${PRETTIER_VERSION} assets/settings/default.json --write"
+    false
+}
+
+cd docs
+pnpm dlx "prettier@${PRETTIER_VERSION}" . --check || {
+    echo "To fix, run from the root of the Zed repo:"
+    echo "  cd docs && pnpm dlx prettier@${PRETTIER_VERSION} . --write && cd .."
+    false
+}