Rework the testMemoryGrowReadWrite and testMemoryGrowZeroInitialSize
tests. Combine the different sized tests (32, 16, 8 bit integers) into a
single base tests, taking in function arguments to specify which
load/store function to call from the module exports.

Also reduced the number of checks made in each test. Previously the test
was asserting on every single valid offset. Now it checks the first 5
and the last 5 of each page of memory. From a quick local test using
`time`, it speeds up this test on x64 from ~40s to ~20s.

There is more work to be done: there are other tests below that also
assert on each offset, we can change those in a future patch.

The goal is to be able to run this on arm simulators
sufficiently quickly, and not require to mark this test as slow.

Bug: v8:7783
Change-Id: I2b17cf1811de6c26332d7e8f91efbbac3e89f6e3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2116601Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66848}