Switch STACK_OF(T) back to std::sort from std::stable_sort

https://boringssl-review.googlesource.com/c/boringssl/+/91687 switched
STACK_OF(T)'s sorting to a stable sort after a recently-added test
exhibited some bugs depending on the sort order.

What was actually going on was that the test made some incorrect
assumptions on how X509_STORE behaved surrounding AKIDs, etc.
https://boringssl-review.googlesource.com/c/boringssl/+/91787 fixed the
test to be less sensitive to this.

std::stable_sort is more likely to allocate and thus depend on the C++
runtime. We do want to allow the C++ runtime in libcrypto, but there are
some hurdles to clear on Android first, so switch back to std::sort.
(At a glance through output on godbolt, libc++'s std::sort might
actually be header-only!)

This does mean that, with the wrong sort order,
X509StoreGet1IssuerMultipleMatches might test against the wrong
baseline. To prevent an unlikely false positive, remove the baselining
check. With the baseline check removed, the test will never have a false
positive, but we might have a false negative. I.e. we might fail to flag
a bug when it should. However, given the number of name collisions we
put in there, and the number of different platforms and STLs we test
against, this is unlikely. (Also that code should be rewritten to use a
hash table anyway.)

Change-Id: I1cca217ac713dbe7758fd4c102d901fdb6ebe177
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/95327
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Lily Chen <chlily@google.com>
Commit-Queue: David Benjamin <davidben@google.com>