[tests] remove several empty oracles

tests/fc_script/oracle/build-callgraph.err

tests/fc_script/oracle/find_fun1.err

tests/fc_script/oracle/find_fun2.err

tests/fc_script/oracle/find_fun3.err

tests/fc_script/oracle/heuristic_list_functions.err

tests/fc_script/oracle/list_files.err

tests/fc_script/oracle/list_functions.err

tests/fc_script/oracle/list_functions2.err

tests/fc_script/oracle/make-wrapper.err

tests/fc_script/oracle/recursions.err

tests/float/oracle/absorb_sav.err

tests/float/oracle/absorb_sav2.err

tests/jcdb/oracle/list_files.err

tests/jcdb/oracle/subdir.err

tests/libc/oracle/fc_libc_sav.err

tests/metrics/oracle/libc_metrics.err

tests/misc/oracle/local_array_non_literal_size.err.oracle

tests/misc/oracle/my_visitor_sav.err

tests/misc/oracle/orphan_emitter_sav.err

tests/saveload/oracle/basic_sav.1.err