tests: add keywords for a couple of HTTP tests

tests/data/test1015

tests/data/test151

tests/data/test152

tests/data/test156

tests/data/test157

tests/data/test159

tests/data/test160

tests/data/test163

tests/data/test164

tests/data/test166

tests/data/test178

tests/data/test180

tests/data/test181

tests/data/test186

tests/data/test189

tests/data/test192

tests/data/test510

tests/data/test512

tests/data/test513

tests/data/test514