Remove compiling and executing non-benchmarking tests from Noir's Earthly `bench-acir-bb` target

[Savio-Sou]

Problem

Running Noir's bench-acir-bb Earthly target currently compiles all Noir tests, both the ones used for benchmarking (i.e. tests in the benchmarks folder) and the ones that are not.

This unnecessarily lengthens benchmarking and benchmark development cycles.

Happy case

Trim down the scope of bench-acir-bb to compile and execute only the Noir programs that are necessary (i.e. those in the benchmarks folder).

[TomAFrench]

This is done inside the build-acir-tests target which is shared between benchmarking and testing which is why it builds both.