Use cross-env

package.json

@@ -32,7 +32,7 @@
 		"website:build:css": "cp ./node_modules/minireset.css/minireset.min.css ./website/styles/",
 		"website:build:ts": "tsc ./website/index.ts",
 		"test": "run-s test:*",
-		"test:jest": "TZ=GMT jest",
+		"test:jest": "cross-env TZ=GMT jest",
 		"test:types": "tsc --noEmit",
 		"format": "prettier --write",
 		"lint:css": "stylelint --fix --max-warnings 0",
@@ -92,6 +92,7 @@
 		"@typescript-eslint/eslint-plugin": "^2.3.3",
 		"@typescript-eslint/parser": "^2.3.3",
 		"babel-loader": "^8.0.6",
+		"cross-env": "^6.0.3",
 		"css-loader": "^3.0.0",
 		"electron": "^6.0.12",
 		"electron-builder": "^22.1.0",

yarn.lock

@@ -3045,6 +3045,13 @@ create-hmac@^1.1.0, create-hmac@^1.1.2, create-hmac@^1.1.4:
     safe-buffer "^5.0.1"
     sha.js "^2.4.8"
 
+cross-env@^6.0.3:
+  version "6.0.3"
+  resolved "https://registry.yarnpkg.com/cross-env/-/cross-env-6.0.3.tgz#4256b71e49b3a40637a0ce70768a6ef5c72ae941"
+  integrity sha512-+KqxF6LCvfhWvADcDPqo64yVIB31gv/jQulX2NGzKS/g3GEVz6/pt4wjHFtFWsHMddebWD/sDthJemzM4MaAag==
+  dependencies:
+    cross-spawn "^7.0.0"
+
 [email protected], cross-spawn@^6.0.0, cross-spawn@^6.0.5:
   version "6.0.5"
   resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-6.0.5.tgz#4a5ec7c64dfae22c3a14124dbacdee846d80cbc4"