Drop support for running CI without rust tag

Author: Greg Soltis

.github/workflows/test.yml

@@ -277,8 +277,6 @@ jobs:
 
       - name: Integration Tests
         run: turbo run test --filter=turborepo-tests-integration --color
-        env:
-          GO_TAG: rust
 
   turborepo_e2e:
     name: Turborepo E2E Tests

cli/turbo.json

@@ -3,7 +3,7 @@
   "extends": ["//"],
   "pipeline": {
     "build": {
-      "env": ["GO_TAG", "RUNNER_OS"],
+      "env": ["RUNNER_OS"],
       "outputs": [
         "../target/debug/go-turbo",
         "../target/debug/turbo",