Add Rust benchmarks for base64, sha512 and regex matching

[Lubrsi]

Initial results on my MacBook Pro M4 14 core machine:

Suite          Test                    Mean ± σ        Range (min … max)
-------------  ----------------------  --------------  -------------------
WasmRustBench  base64-bench.wasm       24.488 ± 0.513  24.030 … 25.320
WasmRustBench  regex-match-bench.wasm  4.632 ± 0.030   4.600 … 4.660
WasmRustBench  sha512-bench.wasm       37.930 ± 0.199  37.650 … 38.100

[gmta]

@Lubrsi there are some conflicts

[Lubrsi]

More up to date results with the current Wasm interpreter:

Suite          Test                                  Mean ± σ        Range (min … max)
-------------  ------------------------------------  --------------  -------------------
WasmRustBench  WasmRustBench/base64-bench.wasm       14.820 ± 0.066  14.750 … 14.880
WasmRustBench  WasmRustBench/regex-match-bench.wasm  2.987 ± 0.035   2.950 … 3.020
WasmRustBench  WasmRustBench/sha512-bench.wasm       20.010 ± 0.082  19.940 … 20.100