E2E Tests: Reduce default timeout

[nwmac]

Fixes #8956

This PR reduces the default cypress timeout used in e2e tests from 60s to 10s.

There are a few tests that need updating to specifically used a longer timeout - a set of timeouts has been created in a utility file and used in the appropriate places.

When a test fails, the test is retried 3 times - so before this PR, a test failure would add 3 minutes to the test run - with this PR it adds 30 seconds.

We can look to reduce the timeout further, but more tests will need to be checked and updated.

This PR also updates a couple of tests to make them more resilient:

• istio test - also attempts to uninstall the charts that are installed
• home page - adds a catch for the support page tests, since this sometimes has an error, due to an error in the Rancher support pages that sometimes happens and causes our test to then fail