Revert "test: restore the environment before each msvc test"

This reverts commit 95f4f7daa1.

src/msvc/__tests__/msvc.test.ts

@@ -2,14 +2,8 @@ import which from "which"
 import { testBin } from "../../utils/tests/test-helpers"
 import { setupMSVC } from "../msvc"
 
-const initial_env = { ...process.env }
-
 jest.setTimeout(300000)
 describe("setup-msvc", () => {
-  beforeEach(() => {
-    process.env = initial_env
-  })
-
   it("should setup msvc 2019", async () => {
     if (process.platform !== "win32") {
       return