Merge 4b568c8023 into d648c2dd06

When a project has both npm and pnpm, using pnpm/action-setup will result in an error: `Multiple versions of pnpm specified`.

The previous implementation was only meant to avoid the "ERR_PNPM_BAD_PM_VERSION" error, but it did not take into account the situation of multiple different package managers.

Signed-off-by: Kevin Cui <bh@bugs.cc>

README.md

@@ -1,7 +1,3 @@
-> ## :warning: Upgrade from v2!
->
-> The v2 version of this action [has stopped working](https://github.com/pnpm/action-setup/issues/135) with newer Node.js versions. Please, upgrade to the latest version to fix any issues.
-
 # Setup pnpm
 
 Install pnpm package manager.

src/install-pnpm/run.ts

@@ -64,6 +64,7 @@ async function readTarget(opts: {
   if (version) {
     if (
       typeof packageManager === 'string' &&
+      packageManager.startsWith('pnpm@') &&
       packageManager.replace('pnpm@', '') !== version
     ) {
       throw new Error(`Multiple versions of pnpm specified: