-Enable blocking queries by default
-Change assertion to check for the last PUT request, not just any request for session destruction from a node page.
Since we've now turned on blocking queries by default this means that a
second GET request is made after the PUT request that we are asserting
for but before the assertion itself, this meant the assertion failed. We
double checked this by turning off blocking queries for this test using
```
And settings from yaml
---
consul:client:
blocking: 0
---
```
which made the test pass again.
As moving forwards blocking queries will be on by default, we didn't
want to disable blocking queries for this test, so we now assert the
last PUT request specifically. This means we continue to assert that the
session has been destroyed but means we don't get into problems of
ordering of requests here
429e27aaee