fix(core): migrate should warn if package does not exist (#23317)

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## Current Behavior
Migrations are a noop if the package can't be fetched

## Expected Behavior
There is a warning if the package doesn't exist

## Related Issue(s)
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Fixes #22308

packages/nx/src/command-line/migrate/migrate.ts

@@ -1053,6 +1053,10 @@ async function getPackageMigrationsUsingInstall(
     }
 
     result = { ...migrations, packageGroup, version: packageJson.version };
+  } catch (e) {
+    logger.warn(
+      `Unable to fetch migrations for ${packageName}@${packageVersion}: ${e.message}`
+    );
   } finally {
     await cleanup();
   }