Support pnpm 2-part "env lockfile" pnpm-lock.yaml files in parseLockFile

change/change-0e3d2bf3-4b0c-4b1b-ad3b-19bff9e9f7a6.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "workspace-tools",
+      "type": "patch",
+      "dependentChangeType": "patch",
+      "comment": "Fix `parseLockFile` throwing on pnpm \"env lockfile\" `pnpm-lock.yaml` files (a 2-document YAML format pnpm writes when `configDependencies` and/or `packageManagerDependencies` are recorded). Only the main (last) document is now parsed; the env document is discarded so its entries never leak into the parsed dependency graph.",
+      "email": "ansteg@microsoft.com"
+    }
+  ]
+}

packages/workspace-tools/src/__fixtures__/basic-pnpm-9-env-lockfile/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "basic-pnpm-9-env-lockfile",
+  "packageManager": "pnpm@12.0.0-beta.1",
+  "version": "0.1.0",
+  "license": "MIT",
+  "private": true,
+  "description": "same as basic-pnpm-9, but with a 2-document 'env lockfile' pnpm-lock.yaml (configDependencies/packageManagerDependencies in a separate leading YAML document); see https://github.com/pnpm/pnpm/pull/10964",
+  "devDependencies": {
+    "@changesets/cli": "^2.14.1",
+    "@testing-library/react": "16.0.1",
+    "is-odd": "3.0.1",
+    "is-positive": "github:kevva/is-positive#97edff6f525f192a3f83cea1944765f769ae2678",
+    "prettier": "2.8.0",
+    "react": "18.3.1",
+    "react-dom": "18.3.1",
+    "typescript": "^4.2.3",
+    "chokidar": "3.6.0"
+  }
+}

packages/workspace-tools/src/__fixtures__/basic-pnpm-9-env-lockfile/patches/is-odd@3.0.1.patch

@@ -0,0 +1,7 @@
+diff --git a/index.js b/index.js
+index 0000000..1111111 100644
+--- a/index.js
++++ b/index.js
+@@ -1,1 +1,2 @@
++// patched for lockfile fixture
+ 'use strict';