Allow using no CIPD pigweed configuration when activating (#20105)

* Allow to set pigweed config via environment

Allow to specify custom pigweed configuration file via PW_CONFIG_FILE,
e.g.
PW_CONFIG_FILE=scripts/environment_no_cipd.json source scripts/bootstrap.sh

This allows to use a custom pigweed config for scripts/activate.sh as
well.

* Disable rosetta in no_cipd config as well

scripts/bootstrap.sh

@@ -26,9 +26,8 @@ _bootstrap_or_activate() {
 
     local _CONFIG_FILE="scripts/environment.json"
 
-    if [ "$_BOOTSTRAP_NAME" = "no_cipd_bootstrap.sh" ]; then
-        _CONFIG_FILE="scripts/environment_no_cipd.json"
-        _BOOTSTRAP_NAME="bootstrap.sh"
+    if [ ! -z "$PW_CONFIG_FILE" ]; then
+        _CONFIG_FILE="$PW_CONFIG_FILE"
     fi
 
     if [ "$_BOOTSTRAP_NAME" = "bootstrap.sh" ] ||

scripts/environment_no_cipd.json

@@ -4,5 +4,6 @@
         "gn_targets": [":python_packages.install"]
     },
     "required_submodules": ["third_party/pigweed/repo"],
+    "rosetta": "never",
     "gni_file": "build_overrides/pigweed_environment.gni"
 }