fix(module-federation): dynamic remotes external to workspace should be skipped correctly #26551 (#26692)

<!-- Please make sure you have read the submission guidelines before
posting an PR -->
<!--
https://github.com/nrwl/nx/blob/master/CONTRIBUTING.md#-submitting-a-pr
-->

<!-- Please make sure that your commit message follows our format -->
<!-- Example: `fix(nx): must begin with lowercase` -->

<!-- If this is a particularly complex change or feature addition, you
can request a dedicated Nx release for this pull request branch. Mention
someone from the Nx team or the `@nrwl/nx-pipelines-reviewers` and they
will confirm if the PR warrants its own release for testing purposes,
and generate it for you if appropriate. -->

## Current Behavior
<!-- This is the behavior we have today -->
Module Federation utils were not checking if the remotes defined
dynamically in the `module-federation.manifest.json` were in the project
graph.



## Expected Behavior
<!-- This is the behavior we should expect with the changes in this PR
-->
Check that the dynamic remotes exist in the project graph before trying
to do work with them

## Related Issue(s)
<!-- Please link the issue being fixed so it gets closed when this is
merged. -->

Fixes #26551

packages/webpack/src/utils/module-federation/get-remotes-for-host.ts

@@ -103,7 +103,7 @@ export function getRemotes(
   );
 
   const knownDynamicRemotes = dynamicRemotes.filter(
-    (r) => !remotesToSkip.has(r)
+    (r) => !remotesToSkip.has(r) && context.projectGraph.nodes[r]
   );
 
   logger.info(