Improve the CPU core count detection

See theofidry/cpu-core-counter#11 for the motivations.

The code should be sensibly the same, the notable differences are:

- fixed the deprecated usage of `hw.ncpu`
- /proc/cpuinfo is check _last_
- nproc is checked first (before was not checked at all, it's considered to be more accurate and less convoluted than cpuinfo though)
- not sure about the `return 2`, but this was not too clear [here](phpstan#514 (review)) neither. I could otherwise change the fallback value to return `1` if `proc_open` doesn't exist and 2 otherwise
- add more ways to find the CPU cores count

composer.json

@@ -10,7 +10,7 @@
 		"clue/ndjson-react": "^1.0",
 		"composer/ca-bundle": "^1.2",
 		"composer/xdebug-handler": "^3.0.3",
-		"fidry/cpu-core-counter": "^0.3.0",
+		"fidry/cpu-core-counter": "^0.3.1",
 		"hoa/compiler": "3.17.08.08",
 		"hoa/exception": "^1.0",
 		"hoa/regex": "1.17.01.13",

src/Process/CpuCoreCounter.php

@@ -17,10 +17,12 @@ public function getNumberOfCpuCores(): int
 		}
 
 		try {
-			return (new FidryCpuCoreCounter())->getCount();
+			$this->count = (new FidryCpuCoreCounter())->getCount();
 		} catch (NumberOfCpuCoreNotFound) {
-			return 1;
+			$this->count = 1;
 		}
+
+		return $this->count;
 	}
 
 }