test: preserve test env

Author: mshanemc

.sfdevrc.json

@@ -0,0 +1,12 @@
+{
+  "wireit": {
+    "test:only": {
+      "command": "nyc mocha \"test/**/*.test.ts\"",
+      "env": {
+        "FORCE_COLOR": "2"
+      },
+      "files": ["test/**/*.ts", "src/**/*.ts", "tsconfig.json", ".mocha*", "test/tsconfig.json", "!*.nut.ts", ".nycrc"],
+      "output": []
+    }
+  }
+}