This change both speeds up specs (less strings to allocate) and helps catch
cases where methods in Discourse are mutating inputs.
Overall we will be migrating everything to use #frozen_string_literal: true
it will take a while, but this is the first and safest move in this direction
We use the `id` of the upload to calculate a `depth` partition in the
filename. This test would fail if your database had a higher seed
because the depth it was looking for was hard coded to 1.
The solution was to not save the records (which is faster anyway) and
specify the `id` of the upload to make the hash deterministic.
This updates tests to use latest rails 5 practice
and updates ALL dependencies that could be updated
Performance testing shows that performance has not regressed
if anything it is marginally faster now.
Sam Saffron
Guo Xiang Tan
Robin Ward
Vinoth Kannan