Fix false negative in project_events_spec.rb

What does this MR do and why?

Fix false negative in project_events_spec.rb.

After using let_it_be, I discovered that the N+1 spec started failing because the control now has less queries.

Unfortunately, it turns out that we do indeed have an N+1 but it's too hard to fix for now.

Screenshots or screen recordings

Before:

$ time be rspec spec/requests/api/project_events_spec.rb
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}

Test environment set up in 5.30844 seconds
...........

Finished in 18.99 seconds (files took 12.72 seconds to load)
11 examples, 0 failures

[TEST PROF INFO] Time spent in factories: 00:05.757 (27.44% of total time)

real	0m32.990s
user	0m22.328s
sys	0m13.458s

After:

$ time be rspec spec/requests/api/project_events_spec.rb
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}

Test environment set up in 4.389354 seconds
...........

Finished in 15.31 seconds (files took 11.82 seconds to load)
11 examples, 0 failures

[TEST PROF INFO] Time spent in factories: 00:02.757 (16.12% of total time)

real	0m28.319s
user	0m18.161s
sys	0m11.981s

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