Merge bitcoin/bitcoin#26158: bench: add "priority level" to the benchmark framework

3e9d0bea8d build: only run high priority benchmarks in 'make check' (furszy)
466b54bd4a bench: surround main() execution with try/catch (furszy)
3da7cd2a76 bench: explicitly make all current benchmarks "high" priority (furszy)
05b8c76232 bench: add "priority level" to the benchmark framework (furszy)
f1593780b8 bench: place benchmark implementation inside benchmark namespace (furszy)

Pull request description:

  This is from today's meeting, a simple "priority level" for the benchmark framework.

  Will allow us to run certain benchmarks while skip non-prioritized ones in `make check`.

  By default, `bench_bitcoin` will run all the benchmarks. `make check`will only run the high priority ones,
  and have marked all the existent benchmarks as "high priority" to retain the current behavior.

  Could test it by modifying any benchmark priority to something different from "high", and
  run `bench_bitcoin -priority-level=high` and/or `bench_bitcoin -priority-level=medium,low`
  (the first command will skip the modified bench while the second one will include it).

  Note: the second commit could be avoided by having a default arg value for the priority
  level but.. an explicit set in every `BENCHMARK` macro call makes it less error-prone.

ACKs for top commit:
  kouloumos:
    re-ACK 3e9d0bea8d
  achow101:
    ACK 3e9d0bea8d
  theStack:
    re-ACK 3e9d0bea8d
  stickies-v:
    re-ACK 3e9d0bea8d

Tree-SHA512: ece59bf424c5fc1db335f84caa507476fb8ad8c6151880f1f8289562e17023aae5b5e7de03e8cbba6337bf09215f9be331e9ef51c791c43bce43f7446813b054

src/bench/descriptors.cpp

@@ -33,4 +33,4 @@ static void ExpandDescriptor(benchmark::Bench& bench)
     ECC_Stop();
 }
 
-BENCHMARK(ExpandDescriptor);
+BENCHMARK(ExpandDescriptor, benchmark::PriorityLevel::HIGH);