Wait for navigation after staking first neuron

[dskloetd]

Motivation

Before you have your first neuron, you can't navigate to the neurons page.
So the first neuron is staked from the staking page and if successful, you automatically navigate to the neurons page.
This caused some flakiness in e2e tests when we try to navigate back after staking the first neuron, but before the redirect happens.
To make this more consistent we should wait for the redirect to happen before returning from stakeFirstNnsNeuron.
Since this happens from StakingPo, we can't wait for NnsNeuronsPo to be present but we can at least wait for StakingPo to be absent.

Changes

Wait for StakingPo to be absent after staking the first NNS neuron.

Tests

On my local machine, e2e/proposals.spec.ts was failing consistently without this change and passed with this change.

Todos

• Add entry to changelog (if necessary).
  not necessary