[roll pigweed] pw_env_setup: Clear PW_ENVIRONMENT_ROOT

Require PW_ENVIRONMENT_ROOT be set before every bootstrap.sh invocation.
It's rarely used, and if set can cause issues when bootstrapping from
one location and then changing to another directory.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/104768

https://pigweed.googlesource.com/pigweed/pigweed
pigweed Rolled-Commits: 2549d702d11e303..53d0f363b0349d0
Roller-URL: https://ci.chromium.org/b/8806821921951309793
Cq-Cl-Tag: roller-builder:pigweed-zephyr-roller
Cq-Cl-Tag: roller-bid:8806821921951309793
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I08d8ae198513a16cef66be1f49bafe9c678d9222
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/104851
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
1 file changed
tree: da4295568fe2d4b204323c229e41295a61206e99
  1. .gitmodules
  2. test.sh