[BOLT][TEST] Fix section order test

.bss section emitted by llvm-bolt (e.g. with instrumentation) is not a
real BSS section, i.e. it takes space in the output file. Hence the
order with respect to .data is not defined. Remove .bss from the test
and fix the buildbot failure.

Reviewed By: Amir

Differential Revision: https://reviews.llvm.org/D135475