interpreter: Correctly handle arguments to benchmark
interpreter: Correctly handle arguments to benchmark

This fixes two separate issues, one is that benchmark warns about
depends and priority; The other is that we passed bad values like
is_parallel into the test and would actually run benchmarks in parallel,
which is bad.

pexip/meson,becm/meson,mesonbuild/meson,pexip/meson,becm/meson,becm/meson,pexip/meson,mesonbuild/meson,pexip/meson,QuLogic/meson,becm/meson,jpakkane/meson,QuLogic/meson,pexip/meson,mesonbuild/meson,QuLogic/meson,QuLogic/meson,QuLogic/meson,mesonbuild/meson,mesonbuild/meson,pexip/meson,becm/meson,jpakkane/meson,mesonbuild/meson,jpakkane/meson,pexip/meson,jpakkane/meson,becm/meson,QuLogic/meson,becm/meson,QuLogic/meson,becm/meson,becm/meson,mesonbuild/meson,jpakkane/meson,pexip/meson,mesonbuild/meson,pexip/meson,QuLogic/meson,mesonbuild/meson,pexip/meson,jpakkane/meson,QuLogic/meson,jpakkane/meson,mesonbuild/meson,jpakkane/meson,becm/meson,jpakkane/meson