fix(ci): use variable reference for AllNodesClientId in e2e test stage

[zanejohnson-azure]

Problem

The ci-logs-dev-aks-all-nodes E2E test was failing on KubePodInventory (and other log-query tests) with:

Failed to query logs: DefaultAzureCredential: failed to acquire a token.
...
ManagedIdentityCredential authentication failed. the requested identity isn't assigned to this resource
{
  "error": "invalid_request",
  "error_description": "Identity not found"
}

Root cause

In .pipelines/azure_pipeline_mergedbranches.yaml, the E2E test stage for the ci-logs-dev-aks-all-nodes cluster was passing the literal string 'AllNodesClientId' as azureClientId instead of the variable reference $(AllNodesClientId).

Every other cluster stage in the file uses the $(...) form (e.g. $(AksWorkLoadIdentityClientId), $(WcusFipsClientId), $(NetworkFlowLogsClientId)), which substitutes the actual workload-identity client GUID from the variable group. The literal string was being plumbed all the way into the test pod as AZURE_CLIENT_ID, so no managed identity matched and token acquisition failed.

Fix

-          azureClientId: 'AllNodesClientId'
+          azureClientId: $(AllNodesClientId)

Note

This assumes a variable named AllNodesClientId exists in the variable group bound to this pipeline (containing the workload-identity client ID GUID for the ci-logs-dev-aks-all-nodes cluster). If it doesn't yet, it needs to be added there alongside the other *ClientId variables — otherwise the substitution will be empty and the test will still fail with the same auth error.