Fix unexpected resize causing test failure

[enjoy-binbin]

Before #12850, we will only try to shrink the dict in serverCron,
which we can control by using a child process, but now every time
we delete a key, the shrink check will be called.

In these test (added in #12802), we meant to disable the resizing,
but druing the delete, the dict will meet the force shrink, like
2 / 128 = 0.015 < 0.2, the delete will trigger a force resize and
will cause the test to fail.

In this commit, we try to keep the load factor at 3 / 128 = 0.023,
that is, do not meet the force shrink.

[enjoy-binbin]

https://github.com/redis/redis/actions/runs/7549063700/job/20552381743#step:6:6511

*** [err]: Redis can trigger resizing in tests/unit/other.tcl
Expected '[Dictionary HT]
Hash table 0 stats (main hash table):
No stats available for empty dictionaries
Hash table 1 stats (rehashing target):
 table size: 4
 number of elements: 1
[Expires HT]
Hash table 0 stats (main hash table):
No stats available for empty dictionaries
' to match '*table size: 128*' (context: type eval line 17 cmd {assert_match "*table size: 128*" [r debug HTSTATS 0]} proc ::test) 

[lyq2333]

I ran the test and it passed before #12850 merged. But the test can pass occasionally even the resizing is triggered depending on the seed of the hash function in main db. 👍