[scudo][standalone] Fix Primary's ReleaseToOS test

Said test was flaking on Fuchsia for non-obvious reasons, and only
for ASan variants (the release was returning 0).

It turned out that the templating was off, `true` being promoted to
a `s32` and used as the minimum interval argument. This meant that in
some circumstances, the normal release would occur, and the forced
release would have nothing to release, hence the 0 byte released.

The symbols are giving it away (note the 1):
```
scudo::SizeClassAllocator64<scudo::FixedSizeClassMap<scudo::DefaultSizeClassConfig>,24ul,1,2147483647,false>::releaseToOS(void)
```

This also probably means that there was no MTE version of that test!

Differential Revision: https://reviews.llvm.org/D88457