Remove aconfigd's dependency on libtempfile

libtempfile is only used for testing in aconfigd so it should be removed
to save some memory for both aconfigd and mmd.

Bug: 404614990
Test: atest build/make/tools/aconfig
Test: manually verify libtempfile.dylib.so doesn't show up in
aconfigd-system showmap anymore

Change-Id: I7d3e20e24295a10c0f5f96071e6c7197bddee5b2