[Perf] Considering Replace StringBuilder with ZString

[workgroupengineering]

ZString

Benchmark

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.19044.1466 (21H2)
Intel Core i7-7700K CPU 4.20GHz (Kaby Lake), 1 CPU, 8 logical and 4 physical cores
.NET SDK=6.0.200-preview.22055.15
  [Host]   : .NET 5.0.13 (5.0.1321.56516), X64 RyuJIT
  .NET 5.0 : .NET 5.0.13 (5.0.1321.56516), X64 RyuJIT
  .NET 6.0 : .NET 6.0.1 (6.0.121.56705), X64 RyuJIT

Method	Job	Runtime	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen 0	Allocated native memory	Native memory leak	Gen 1	Gen 2	Allocated
ZStringFormatInt	.NET 5.0	.NET 5.0	8.041 ms	0.0570 ms	0.0445 ms	8.032 ms	0.89	0.02	281.2500	-	-	281.2500	281.2500	1,397 KB
AppendFormatInt	.NET 5.0	.NET 5.0	9.057 ms	0.1811 ms	0.2155 ms	9.018 ms	1.00	0.00	906.2500	-	-	562.5000	218.7500	4,315 KB
AppendFormatString	.NET 5.0	.NET 5.0	2.955 ms	0.0590 ms	0.1064 ms	2.938 ms	0.33	0.02	640.6250	-	-	500.0000	375.0000	3,134 KB
ZStringFormatString	.NET 5.0	.NET 5.0	5.429 ms	0.0886 ms	0.1121 ms	5.417 ms	0.60	0.02	312.5000	-	-	312.5000	312.5000	2,292 KB
ZStringFormatInt	.NET 6.0	.NET 6.0	8.245 ms	0.1606 ms	0.1850 ms	8.189 ms	0.91	0.02	187.5000	-	-	187.5000	187.5000	977 KB
AppendFormatInt	.NET 6.0	.NET 6.0	8.542 ms	0.1834 ms	0.5380 ms	8.391 ms	0.93	0.06	890.6250	-	-	562.5000	242.1875	4,315 KB
AppendFormatString	.NET 6.0	.NET 6.0	2.395 ms	0.0440 ms	0.0411 ms	2.392 ms	0.27	0.01	636.7188	-	-	515.6250	367.1875	3,134 KB
ZStringFormatString	.NET 6.0	.NET 6.0	4.290 ms	0.0836 ms	0.1172 ms	4.287 ms	0.47	0.02	320.3125	-	-	320.3125	320.3125	2,385 KB

[jeromelaban]

Unfortunately, in most cases, it undesirable for generators to take an external dependency... We'll have to live with StringBuilder until it gets improved in later .NET builds.