These parsing strings are tiny, less than 64 bytes all the time. Just
stack allocate the buffer. Makes it safer to use during extenuating
circumstances as well, like SIGBUS and SIGSEGV.
String parsing was adding a newline but then we failed to use it. I
don't think it caused any issues considering how infrequent instant
profiler objects are used.
It is not an external component, and it makes paths needlessly long.
Ryan seemed amenable to this when we discussed on IRC earlier.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>