More tests are being added to the search e2e testing suite and when these tests run concurrently multiple search indexes are built on the same mongot at the same time. This has led to out of memory errors on some machines. We need to change our testing strategy in the e2e tests to support all of the new tests being added. We have to either 

1. run fewer tests concurrently
2. make smaller indexes
3. increase the size of the machine
4. wait and retry tests if they fail with an out of memory error

We should try and find a more permanent solution so we don't keep hitting this problem as more tests are added

See the attached ticket for full details.