Brush up readme

Author: devizer

README.md

@@ -66,7 +66,7 @@ Here is a summary of CPU usage precision. In general, it depends on OS and versi
 | Linux, ARMv7 H3 CPU, 1.30GHz, kernel 6.13                                  |        _4,000 μs_ |
 | Mac OS 10.14, Xeon E5-2697 v2 @ 2.70GHz                                    |           14.0 μs |
 | Mac OS 15, Apple M1                                                        |            3.0 μs |
-| FreeBSD 12, .NET Core 2.0, Xeon E3-1270 v2 @ 3.50GHz, pseudo kernel 2.6.32 |            3.0 μs |
+| FreeBSD 12, .NET Core, Xeon E3-1270 v2 @ 3.50GHz, pseudo kernel 2.6.32     |            3.0 μs |
 | FreeBSD 12, Mono 5.1, Xeon E3-1270 v2 @ 3.50GHz, native BSD 12             |            1.9 μs |
 
 Detailed histograms of precision are produced by PrecisionTest.cs