Migrate dict.c unit tests to new test framework

[jay-tau]

Fixes #428 for dict.c

Currently, all tests are in a single function. Before splititng it into induvidual unit tests, I wanted to ensure that everything was working as expected.

Currently, the 3rd test is raising a SIGSEV.
By performing print debugging, I have concluded that the issue lies in this line.
This type is declared in monotonic.h, so I am unsure why it is leading to a segfault.
Note, I believe it might be the same issue described by @jazelly here

Because of the issue with the monotime timer, all calls to dictRehashMicroseconds are leading to a segfault.

@madolson I would appreciate your thoughts. I am currently unsure how to proceed.
Please do let me know if I can provide any more information in this regard.

[flowerysong]

This feels like it's probably a missing monotonicInit(), resulting in getMonotonicUs still being null and the call to elapsedStart() segfaulting.

valkey/src/server.c

Line 6633 in ae2d421

monotonicInit(); /* Required for dict tests, that are relying on monotime during dict rehashing. */

is where this was called for the old test framework.

[jay-tau]

Thank you @flowerysong. Initialising monotonic as you suggested solved the issue :D

Now that this is fixed, I am able to think about how to structure the tests:

• Would it be better to go ahead and break each test into a separate function? Because each test depends on the result of the previous ones right now.
• Also, what would be the best way to handle running the benchmarks? Should they have an assert statement, to make sure that the time taken is within some expected value? I think this might not be viable considering the variety of hardware that the tests might run on.

Note: I have taken a look at some of the other unit testing PRs and didn't observe a clear pattern on when to split the tests into multiple functions. However, from a logical standpoint, I think it would make sense to have individual tests that do not rely on the TEST directive, rather than one single monolithing test.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.23%. Comparing base (ae2d421) to head (17a40cf).
Report is 5 commits behind head on unstable.

Additional details and impacted files

@@             Coverage Diff              @@
##           unstable     #673      +/-   ##
============================================
+ Coverage     70.03%   70.23%   +0.20%     
============================================
  Files           110      110              
  Lines         60076    60084       +8     
============================================
+ Hits          42076    42202     +126     
+ Misses        18000    17882     -118     

Files	Coverage Δ
src/server.c	88.54% <ø> (ø)

... and 13 files with indirect coverage changes