chore: Test performance (#5786)

.jestconfig.json

@@ -1,5 +1,6 @@
 {
   "workerIdleMemoryLimit": "0.75",
+  "maxWorkers": "1",
   "projects": [
     {
       "displayName": "server",
@@ -13,8 +14,9 @@
         "<rootDir>/server/test/env.ts"
       ],
       "setupFilesAfterEnv": ["<rootDir>/server/test/setup.ts"],
-      "testEnvironment": "node",
-      "runner": "@getoutline/jest-runner-serial"
+      "globalSetup": "<rootDir>/server/test/globalSetup.ts",
+      "globalTeardown": "<rootDir>/server/test/globalTeardown.ts",
+      "testEnvironment": "node"
     },
     {
       "displayName": "app",